Coating solution for forming ultraviolet-absorbing film, and ultraviolet-absorbing glass article

ABSTRACT

To provide a coating solution for forming an ultraviolet-absorbing film which has mechanical durability such as abrasion resistance and which is little susceptible to deterioration of the ultraviolet-absorbing ability by use for a long period of time, and an ultraviolet-absorbing glass article having an ultraviolet-absorbing film formed by using such a coating solution, which has mechanical durability such as abrasion resistance and which is little susceptible to deterioration of the ultraviolet-absorbing ability by use for a long period of time. 
     A coating solution which comprises a component derived from an epoxidized organooxysilane compound, a component derived from an organooxysilane compound which is a reaction product of a hydroxylated benzophenone compound and an epoxidized organooxysilane compound, and a component derived from an organooxysilane compound other than the above both organooxysilane compounds, and an ultraviolet-absorbing glass article obtained by using the coating solution.

TECHNICAL FIELD

The present invention relates to a coating solution for forming anultraviolet-absorbing film on the surface of an article such as glass,and an ultraviolet-absorbing glass article having anultraviolet-absorbing film formed by using such a coating solution.

BACKGROUND ART

In recent years, it has been attempted that on a transparent substratesuch as window glass for a vehicle such as an automobile or window glassfor a house or building, an ultraviolet-absorbing film is formed as acoating film which has an ability to absorb ultraviolet rays enteringinto the vehicle or room therethrough and which has mechanicaldurability such as abrasion resistance.

In order to obtain an ultraviolet-absorbing coating film having highabrasion resistance and ultraviolet-absorbing ability, it has beenattempted to form a silica-type ultraviolet-absorbing film on asubstrate by using a coating solution having an organicultraviolet-absorbing agent blended to a silane compound. For example,Patent Document 1 discloses that a coating solution comprising a siliconalkoxide and a water-soluble organic polymer such as polyethylene glycoland further containing an ultraviolet absorber or an organic colorant,is applied on a glass plate, followed by curing to obtain anultraviolet-absorbing film made of an organic/inorganic composite film.However, with the silica-type ultraviolet-absorbing film as disclosed inPatent Document 1, absorption of long wavelength ultraviolet raysrequired by the present invention has not been accomplished although ithas mechanical durability such as abrasion resistance, and if it isattempted to add the ultraviolet-absorber in a high concentration inorder to absorb ultraviolet rays having long wavelengths, there havebeen problems such that deterioration in the mechanical durability andbleeding out of the ultraviolet absorber from the film under highhumidity tend to occur, whereby the ultraviolet-absorbing ability cannotbe maintained for a long period of time.

As a technique to solve the problem of bleeding out of the ultravioletabsorber in the silica type ultraviolet-absorbing film, Patent Document2 discloses an attempt to form a silica-type ultraviolet-absorbing filmby using a coating solution having blended to a silane compound areaction product of a silane compound with an organic compound having anultraviolet-absorbing ability. The silica-type ultraviolet-absorbingfilm as disclosed in Patent Document 2 is free from bleeding out of theultraviolet absorber from the film and may accomplish absorption of thelong wavelength ultraviolet rays desired by the present invention, butit has had a problem that cracking resistance and abrasion resistanceare not sufficient especially when such a silica-typeultraviolet-absorbing film is formed on glass.

Therefore, an ultraviolet-absorbing film has been desired which is lesssusceptible to deterioration of the ultraviolet-absorbing ability by usefor a long period of time, while securing mechanical durability such asabrasion resistance.

PRIOR ART DOCUMENTS Patent Documents

-   Patent Document 1: WO2006/137454-   Patent Document 2: JP-A-2001-89710

DISCLOSURE OF INVENTION Technical Problem

The present invention has been made to solve the above problem, and itis an object of the present invention to provide a coating solution forforming an ultraviolet-absorbing film which has mechanical durabilitysuch as abrasion resistance and which is little susceptible todeterioration of the ultraviolet-absorbing ability by use for a longperiod of time, and an ultraviolet-absorbing glass article having anultraviolet-absorbing film which is formed by using such a coatingsolution and which has mechanical durability such as abrasion resistanceand is little susceptible to deterioration of the ultraviolet-absorbingability by use for a long period of time.

Solution to Problem

The present invention provides a coating solution for forming anultraviolet-absorbing film and an ultraviolet-absorbing glass articlehaving the following constructions.

[1] A coating solution for forming an ultraviolet-absorbing film, whichcomprises a combination of the following three components:

-   -   a component derived from an epoxidized organooxysilane compound        (a),    -   a component derived from an organooxysilane compound (b) which        is a reaction product of a hydroxylated benzophenone compound        and an epoxidized organooxysilane compound, and    -   a component derived from an organooxysilane compound (c) other        than the above (a) and (b),        wherein each of the above three components is the corresponding        organooxysilane compound of the above (a), (b) or (c), or a        constituting component of a partially hydrolyzed condensate of        at least the corresponding organooxysilane compound of the above        (a), (b) or (c).

[2] The coating solution for forming an ultraviolet-absorbing filmaccording to [1], wherein the proportions of the component derived fromthe organooxysilane compound (a), the component derived from theorganooxysilane compound (b) which is a reaction product of ahydroxylated benzophenone compound and an epoxidized organooxysilanecompound, and the component derived from the organooxysilane compound(c) other than the above (a) and (b) are such proportions that, based on100 parts by mass of the total solid content of the component derivedfrom the organooxysilane compound (a), the component derived from theorganooxysilane compound (b) which is a reaction product of ahydroxylated benzophenone compound and an epoxidized organooxysilanecompound, and the component derived from the organooxysilane compound(c) other than the above (a) and (b), the component derived from theorganooxysilane compound (a) is from 5 to 50 parts by mass, thecomponent derived from the organooxysilane compound (b) is from 10 to 50parts by mass, and the component derived from the organooxysilanecompound (c) is from 40 to 80 parts by mass.

[3] The coating solution for forming an ultraviolet-absorbing filmaccording to [1] or [2], which contains at least one member selectedfrom polyepoxides and glycerin.

[4] The coating solution for forming an ultraviolet-absorbing filmaccording to [3], wherein the content of said at least one memberselected from polyepoxides and glycerin is from 0.1 to 20 parts by mass,based on 100 parts by mass of the total solid content of the componentderived from the organooxysilane compound (a), the component derivedfrom the organooxysilane compound (b) which is a reaction product of ahydroxylated benzophenone compound and an epoxidized organooxysilanecompound, and the component derived from the organooxysilane compound(c) other than the above (a) and (b).

[5] The coating solution for forming an ultraviolet-absorbing filmaccording to any one of [1] to [4], which contains an acid having aprimary proton pKa of from 1.0 to 5.0 in a proportion of from 0.005 to5.0 mol/kg as the molar concentration, based on the total mass of thecoating solution, of the proton when the primary proton of the acid iscompletely dissociated.

[6] The coating solution for forming an ultraviolet-absorbing filmaccording to any one of [1] to [5], which contains fine particles ofsilica in a proportion of from 0.5 to 50 parts by mass, based on 100parts by mass of the total solid content of the component derived fromthe organooxysilane compound (a), the component derived from theorganooxysilane compound (b) which is a reaction product of ahydroxylated benzophenone compound and an epoxidized organooxysilanecompound, and the component derived from the organooxysilane compound(c) other than the above (a) and (b), and water in a proportion of from8 to 20 equivalents by molar ratio to the amount, calculated as SiO₂, ofthe component derived from the organooxysilane compound (c).

[7] The coating solution for forming an ultraviolet-absorbing filmaccording to any one of [1] to [6], wherein the content of the componentderived from the organooxysilane compound (c) is from 1 to 10 mass % asthe SiO₂ content when silicon atoms contained in this component arecalculated as SiO₂.

[8] An ultraviolet-absorbing glass article comprising a glass substrateand an ultraviolet-absorbing film formed on at least part of the glasssubstrate surface by using the coating solution for forming anultraviolet-absorbing film as defined in any one of [1] to [7].

[9] The ultraviolet-absorbing glass article according to [8], whereinthe transmittance of light having a wavelength of 380 nm through theglass article is at most 7.0%.

[10] The ultraviolet-absorbing glass article according to [8] or [9],wherein when an abrasion test of 1,000 rotations with a CS-10F abrasivewheel is applied against the surface of the ultraviolet-absorbing filmin accordance with JIS-R3212 (1998), the increase in the haze after thetest as compared to before the test is at most 5.0%.

Advantageous Effects of Invention

By using the coating solution for forming an ultraviolet-absorbing filmof the present invention, it is possible to form anultraviolet-absorbing film which has mechanical durability such asabrasion resistance and which is little susceptible to deterioration ofthe ultraviolet-absorbing ability by use for a long period of time, andthe ultraviolet-absorbing glass article having such anultraviolet-absorbing film has durability for a long period of time withrespect to not only the mechanical durability but also theultraviolet-absorbing ability.

DESCRIPTION OF EMBODIMENTS

Now, the present invention will be described with reference to itsembodiments.

[Coating Solution for Forming Ultraviolet-Absorbing Film of the PresentInvention]

The coating solution for forming an ultraviolet-absorbing film of thepresent invention comprises a component derived from an epoxidizedorganooxysilane compound (a), a component derived from anorganooxysilane compound (b) which is a reaction product of ahydroxylated benzophenone compound and an epoxidized organooxysilanecompound (hereinafter referred to also as “silylated benzophenonecompound”, as the case requires), and a component derived from anorganooxysilane compound (c) other than the above (a) and (b). Here,each of the above organooxysilane compounds (a) to (c) is a compoundhaving at least two organooxy groups bonded to a silicon atom.

In the present invention, a component derived from an organooxysilanecompound is, e.g. in the case of a component derived from anorganooxysilane compound (a), meant for a component which includes notonly the organooxysilane compound (a) itself but also a constitutingunit of the organooxysilane compound (a) in a partially hydrolyzedcondensate containing the organooxysilane compound (a) as theconstituting unit or in a partially hydrolyzed co-condensate containingthe organooxysilane compound (a) and the organooxysilane compound (b)and/or (c) as constituting units.

Therefore, the coating solution for forming an ultraviolet-absorbingfilm of the present invention may contain, as components derivedrespectively from the organooxysilane compounds (a) to (c), theorganooxysilane compounds (a) to (c) themselves or the respectivepartially hydrolyzed condensates of the organooxysilane compounds (a) to(c). Otherwise, the coating solution for forming anultraviolet-absorbing film of the present invention may contain apartially hydrolyzed co-condensate of optional two types among theorganooxysilane compounds (a) to (c), and the remaining one type.Otherwise, the coating solution for forming an ultraviolet-absorbingfilm of the present invention may contain a partially hydrolyzedco-condensate of the three types of the organooxysilane compounds (a) to(c). Such a partially hydrolyzed condensate or partially hydrolyzedco-condensate will be described later in the description of eachorganooxysilane compound.

In a finally cured product of the organooxysilane compounds (a) to (c),the organooxysilane compounds (a) to (c) as well as the constitutingunits of the organooxysilane compounds (a) to (c) which constitute theabove mentioned partially hydrolyzed condensate or partially hydrolyzedco-condensate, are considered to become the same curedproduct-constituting units. It is essential for the coating solution forforming an ultraviolet-absorbing film of the present invention tocomprise, in combination, the respective components derived from threetypes of the organooxysilane compounds (a) to (c) irrespective ofwhether they are organooxysilane compounds themselves or constitutingunits in the partially hydrolyzed condensates or partially hydrolyzedco-condensates.

<Epoxidized Organooxysilane Compound (a)>

The epoxidized organooxysilane compound (a) in the present invention isnot particularly limited so long as it is an organooxysilane compoundhaving an epoxidized organic group bonded to a silicon atom, butpreferably, an organooxysilane compound represented by the followingformula (A) may be mentioned. Here, the organic compound bonded to asilicon atom is meant for an organic group wherein an atom bonded to thesilicon atom is a carbon atom. Further, hereinafter, the epoxidizedorganooxysilane compound (a) may be referred to also as anorganooxysilane compound (a).

R¹ _(a)SiR² _(b)(OR³)_(4−(a+b))  (A)

In the formula (A), R¹ is an epoxidized organic group, R² is a C₁₋₁₀alkyl group or an aryl group, R³ is a hydrogen atom or a C₁₋₁₀monovalent hydrocarbon group which may contain an oxygen atom, a is 1 or2, and b is 0 or 1, provided that a+b is 1 or 2.

In the above formula (A), R¹ is an epoxidized organic group, and thenumber of epoxy groups in the organic group or the type of the organicgroup itself is not particularly limited. Specifically, however, it maybe a C₂₋₁₅ linear or branched alkyl group which may have an oxygen atomand which has one epoxy group or epoxy group-containing cycloalkyl groupat its terminal. Among them, in the present invention, a3-glycidoxypropyl group represented by the following formula (1-1), a5,6-epoxyhexyl group represented by the following formula (1-2), a9,10-epoxydecyl group represented by the following formula (1-3) and a2-(3,4-epoxycyclohexyl)ethyl group represented by the following formula(1-4) are, for example, preferred, and from the viewpoint of thereactivity with a silane compound, the 3-glycidoxypropyl group and the2-(3,4-epoxycyclohexyl)ethyl group are, for example, particularlypreferred.

In the above formula (A), the number of epoxidized organic groups R¹bonded to the silicon atom is represented by a. In the compoundrepresented by the formula (A), the number represented by a is 1 or 2,but in the present invention, an epoxidized organooxysilane compoundwherein a is 1, is preferably employed.

In the above formula (A), R² is a C₁₋₁₀ alkyl group or an aryl group,and specifically, it may, for example, be a methyl group, an ethylgroup, a propyl group, a hexyl group, a decyl group or a phenyl group.Preferred R² is an alkyl group having at most 4 carbon atoms. In theabove formula (A), the number of R² represented by b i.e. the number ofC₁₋₁₀ alkyl groups or aryl groups bonded to the silicon atom, is 0 or 1,but from the viewpoint of the abrasion resistance, b=0 is preferred.

In the above formula (A), R³ is a hydrogen atom or a C₁₋₁₀ monovalenthydrocarbon group which may contain an oxygen atom. Such a monovalenthydrocarbon group may, for example, be a C₁₋₁₀ alkyl group, a C₂₋₁₀alkenyl group or alkynyl group, a C₅ or C₆ cycloalkyl group, a C₂₋₁₀acyl group, a C₆₋₁₀ aryl group or a C₇₋₁₀ aralkyl group, andspecifically, it may, for example, be a methyl group, an ethyl group, apropyl group, an isopropyl group, a butyl group, a hexyl group, a phenylgroup, an isopropenyl group, a methoxyethyl group or an acetyl group.The monovalent hydrocarbon group containing an oxygen atom may, forexample, be a C₂₋₁₀ alkoxyalkyl group, an acyloxyalkyl group, or analkoxycarbonylalkyl group, and specifically, it may, for example, be a2-methoxyethyl group. Among them, in the present invention, an alkylgroup having at most 4 carbon atoms such as a methyl group, an ethylgroup or an isopropyl group, is particularly preferred from theviewpoint of the hydrolytic rate or the stability of the coatingsolution.

Further, in the above formula (A), a+b is 1 or 2, whereby the number ofOR³ bonded to the silicon atom, as represented by 4−a−b, is 3 or 2.

Such an epoxidized organooxysilane compound represented by the aboveformula (A) may specifically, be for example,3-glycidoxypropyltrimethoxysilane,3-glycidoxypropylmethyldimethoxysilane,3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane,2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane,2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane,2-(3,4-epoxycyclohexyl)ethyltriethoxysilane or2-(3,4-epoxycyclohexyl)ethylmethyldiethoxysilane.

In the present invention, from the viewpoint of the solubility in othercomponents contained in the coating solution for forming anultraviolet-absorbing film of the present invention, the reactivity withthe after-described organooxysilane compound (c), etc., the aboveorganooxysilane compound (a) is more preferably e.g.3-glycidoxypropyltrimethoxysilane,2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane,3-glycidoxypropylmethyldimethoxysilane or2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane.

The organooxysilane compound (a) to be used in the present invention isconsidered to serve as a binder to impart cracking resistance whilemaintaining the desired abrasion resistance when the film is made thick.

<Organooxysilane Compound (b)>

The organooxysilane compound (b) in the present invention, i.e. anorganooxysilane compound (b) which is a reaction production of ahydroxylated benzophenone compound and an epoxidized organooxysilanecompound, is a component having an ultraviolet-absorbing ability by theaction of the hydroxylated benzophenone compound as a starting material.The reaction product of the hydroxylated benzophenone compound and theepoxidized organooxysilane compound (referred to also as a silylatedbenzophenone compound, as mentioned above) is assembled in a siliconoxide type network having a crosslinked structure formed from anorganooxysilane compound, whereby the residue of the hydroxylatedbenzophenone compound is fixed in the network. Thus, the hydroxylatedbenzophenone compound is prevented from bleeding out, whereby it is madepossible that the ultraviolet-absorbing film maintains theultraviolet-absorbing ability over a long period of time. Here, thesilylated benzophenone compound has the same organooxysilyl group as theorganooxysilane compound (a) and thus is regarded as one type of theorganooxysilane compound.

The hydroxylated benzophenone compound as a starting material for theabove silylated benzophenone compound may be any compound so long as itis a compound having a benzophenone skeleton and having a hydroxy group,but in the present invention, a benzophenone compound having from 2 to 4hydroxy groups, represented by the following formula (B), is preferablyused from such a viewpoint that it has an excellentultraviolet-absorbing ability even after being silylated. From theviewpoint of the ultraviolet-absorbing ability, particularly from theviewpoint of the ability for absorbing ultraviolet rays with awavelength of up to 380 nm, the number of hydroxyl groups in thehydroxylated benzophenone compound is more preferably 3 or 4.

In the formula, each of Xs which may be the same or different from oneanother, is a hydrogen atom or a hydroxy group, provided that at leastone of them is a hydroxy group.

Further, among the hydroxylated benzophenone compounds represented bythe above formula (B), in the present invention, a2,4-dihydroxybenzophenone represented by the following formula (2-1), a2,2′,3 (or 4,5,6)-trihydroxybenzophenone represented by the formula(2-2), a 2,2′,4,4′-tetrahydroxybenzophenone represented by the formula(2-3), etc. are more preferred, and the2,2′,4,4′-tetrahydroxybenzophenone is particularly preferred. In thereaction of silylating the hydroxylated benzophenone compound, one ofsuch hydroxylated benzophenone compounds may be used alone or two ormore of them may be used in the form of a mixture.

The epoxidized organooxysilane compound to be used for the reaction forsilylating such a hydroxylated benzophenone compound may be the samecompound as the above mentioned organooxysilane compound (a). Preferredmay be the compound represented by the above formula (A), but morepreferred may, for example, be 3-glycidoxypropyltrimethoxysilane,3-glycidoxypropylmethyldimethoxysilane,3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane,epoxycyclohexyl)ethyltrimethoxysilane,2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane,epoxycyclohexyl)ethyltriethoxysilane or2-(3,4-epoxycyclohexyl)ethylmethyldiethoxysilane.

Among them, particularly preferred as the epoxidized organooxysilanecompound from the viewpoint of e.g. the solubility in the coatingsolution may, for example, be 3-glycidoxypropyltrimethoxysilane,2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane,3-glycidoxypropylmethyldimethoxysilane or2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane. In the reaction forsilylating the hydroxylated benzophenone compound, one of suchepoxidized organooxysilane compounds may be used alone, or two or moreof them may be used in the form of a mixture.

As the method for obtaining the reaction product of the hydroxylatedbenzophenone compound and the epoxidized organooxysilane compound, ausual method for a silylation reaction may be used without anyparticular restriction, and specifically, the following method may bementioned.

At least one of the hydroxylated benzophenone compounds and at least oneof the epoxidized organooxysilane compounds are reacted, if necessary,in the presence of a catalyst. The amount of the epoxidizedorganooxysilane compound to be used for the reaction is not particularlylimited, but it is preferably from 0.5 to 5.0 mol, more preferably from1.0 to 3.0 mol, per 1 mol of the hydroxylated benzophenone compound. Ifthe amount of the epoxidized organooxysilane compound is less than 0.5mol per 1 mol of the hydroxylated benzophenone compound, in a case wherethe reaction product is to be added to the coating solution for formingan ultraviolet-absorbing film of the present invention, the solubilityis likely to be low, and the hydroxylated benzophenone compound notsilylated will be present substantially in the film and will be likelyto bleed out. On the other hand, if the amount of the epoxidizedorganooxysilane compound exceeds 5.0 mol per 1 mol of the hydroxylatedbenzophenone compound, the absolute amount of the hydroxylatedbenzophenone compound relating to the ultraviolet-absorption becomessmall, whereby the ultraviolet-absorbing ability tends to be low.

Further, in a case where in this reaction, the epoxidizedorganooxysilane compound is excessively added, a non-reacted epoxidizedorganooxysilane compound will remain without being reacted with thehydroxylated benzophenone compound, and such a non-reacted epoxidizedorganooxysilane compound will function as the above-mentionedorganooxysilane compound (a), and therefore it is not necessary toremove the non-reacted epoxidized organooxysilane compound bypurification. Here, such a non-reacted epoxidized organooxysilanecompound is added as a blend amount of the organooxysilane compound (a),when it is blended to the after-described coating solution for formingan ultraviolet-absorbing film of the present invention.

The catalyst to be used for the silylation reaction is preferably aquaternary ammonium salt as disclosed in JP-A-58-10591. The quaternaryammonium salt may, for example, be tetramethylammonium chloride,tetraethylammonium chloride, benzyltrimethylammonium chloride orbenzyltriethylammonium chloride.

The amount of the catalyst to be added to the reaction system is notparticularly limited, but it is preferably from 0.005 to 10 parts bymass, more preferably from 0.01 to 5 parts by mass, per 100 parts bymass of the total of the hydroxylated benzophenone compound and theepoxidized organooxysilane compound. If the amount of the catalyst to beadded is less than 0.005 part by mass per 100 parts by mass of the totalof the hydroxylated benzophenone compound and the epoxidizedorganooxysilane compound, it tends to take long time for the reaction,and if it exceeds 10 parts by mass, when such a reaction product isadded to the coating solution for forming an ultraviolet-absorbing filmof the present invention, the catalyst is likely to lower the stabilityof the coating solution.

The above silylation reaction may be carried out by heating the mixtureof the hydroxylated benzophenone compound and the epoxidizedorganooxysilane compound preferably in the above mentioned proportionsin the presence of the catalyst within a temperature range of from 50 to150° C. for from 4 to 20 hours. This reaction may be carried out in theabsence of a solvent capable of dissolving both the hydroxylatedbenzophenone compound and the epoxidized organooxysilane compound. Amethod of employing the solvent is preferred from the viewpoint ofhandling efficiency or control efficiency of the reaction. Such asolvent may, for example, be toluene, xylene, ethyl acetate or butylacetate. Further, the amount of the solvent to be used may, for example,be at a level of from 10 to 300 parts by mass per 100 parts by mass ofthe total of the hydroxylated benzophenone compound and the epoxidizedorganooxysilane compound.

The silylated benzophenone compound to be preferably used in the presentinvention, i.e. the organooxysilane compound (b), may, for example, be areaction product obtained by reacting one or two hydroxy groups of abenzophenone compound containing at least three hydroxy groups with anepoxy group of an epoxidized organooxysilane compound, more preferably4-(2-hydroxy-3-(3-trimethoxysilyl)propoxy)propoxy)-2,2′,4′-trihydroxybenzophenonerepresented by the following formula (3-1). Here, in the followingformula (3-1), Me represents a methyl group.

<Organooxysilane Compound (c)>

The organooxysilane compound (c) in the present invention is anorganooxysilane compound other than the above (a) and (b), i.e. anorganooxysilane compound not containing an epoxy group or a residualgroup of a hydroxylated benzophenone compound. The organooxysilanecompound (c) is not particularly limited so long as it is anorganooxysilane compound not containing an epoxy group or a residualgroup of a hydroxylated benzophenone compound, but in the presentinvention, a silane compound represented by the following formula (C)may preferably be mentioned.

R⁴ _(m)SiR⁵ _(n)(OR⁶)_(4−(m+n))  (C)

In the above formula (C), R⁴ is a C₁₋₁₀ substituted or unsubstitutedmonovalent hydrocarbon group, R⁵ is a C₁₋₁₀ alkyl group or an arylgroup, R⁶ is a hydrogen atom or a C₁₋₁₀ monovalent hydrocarbon groupwhich may contain an oxygen atom, and each of m and n is 0, 1 or 2,provided that m+n is 0, 1 or 2. However, the above R⁴ is not an organicgroup containing an epoxy group or is not an organic group having aresidue of a hydroxylated benzophenone compound.

In the above formula (C), R⁴ may specifically be a C₁₋₁₀ alkyl group, anaryl group, a halogenated alkyl group, a halogenated aryl group, analkenyl group or a substituted monovalent hydrocarbon group having someor all of hydrogen atoms of such a group substituted by a substituentcontaining no epoxy group, such as a (meth)acryloxy group, a mercaptogroup, an amino group or a cyano group. More specifically, it may, forexample, be an alkyl group such as a methyl group, an ethyl group, apropyl group, an isopropyl group, a butyl group, a hexyl group, a decylgroup or a cyclohexyl group, an aryl group such as a phenyl group or aphenethyl group, a halogenated alkyl group such as a 3-chloropropylgroup, a 3,3,3-trifluoropropyl group or a3,3,4,4,5,5,6,6,6-nonafluorohexyl group, a halogenated aryl group suchas a p-chlorophenyl group, an alkenyl group such as a vinyl group, anallyl group, a 9-decenyl group or a p-vinylbenzyl group, a(meth)acryloxy group-containing organic group such as a3-methacryloxypropyl group or a 3-acryloxypropyl group, a mercaptogroup-containing organic group such as a 3-mercaptopropyl group or ap-mercaptomethylphenylethyl group, an amino group-containing organicgroup such as a 3-aminopropyl group or a (2-aminoethyl)-3-aminopropylgroup, or a cyano group-containing organic group such as a 2-cyanoethylgroup. Here, the term “(meth)acryl . . . ” of e.g. a (meth)acryloxygroup, means both “acryl . . . ” and “methacryl . . . ”.

Further, in the present invention, R⁴ may preferably be e.g. a3-methacryloxypropyl group or a 3-acryloxypropyl group. In the aboveformula (C), the number of R⁴ bonded to a silicon atom, represented bym, is 0, 1 or 2, but in the present invention, m=0 is preferred from theviewpoint of the abrasion resistance.

In the above formula (C), R⁵ is the same group as R² in the aboveformula (A), and R⁶ is the same group as R³ in the above formula (A). R⁵is preferably an alkyl group having at most 4 carbon atoms, and R⁶ ispreferably an alkyl group having at most 4 carbon atoms. In the aboveformula (C), the number of R⁵ bonded to the silicon atom, represented byn, is 0, 1 or 2. Further, m+n is 0, 1 or 2. Therefore, the number of OR⁶bonded to the silicon atom in the above formula (C), represented by4−m−n, is 4, 3 or 2. That is, the silane compound represented by theabove formula (C) to be used in the present invention, functions as abinder having an adhesive property.

The silane compound represented by the above formula (C) mayspecifically be a dialkoxysilane or diacyloxysilane, a trialkoxy ortriacyloxysilane, or a tetraalkoxysilane, as exemplified below.

The dialkoxysilane or diacyloxysilane may specifically be e.g.dimethyldimethoxysilane, dimethyldiethoxysilane,dimethyldi(2-methoxyethoxy)silane, dimethyldiacetoxysilane,dimethyldipropoxysilane, dimethyldiisopropenoxysilane,dimethyldibutoxysilane, vinylmethyldimethoxysilane,vinylmethyldiethoxysilane, vinylmethyldiacetoxysilane,vinylmethyldi(2-methoxyethoxy)silane, vinylmethyldiisopropenoxysilane,phenylmethyldimethoxysilane, phenylmethyldiethoxysilane,phenylmethyldiacetoxysilane, 3-chloropropylmethyldimethoxysilane,3-chloropropylmethyldiethoxysilane, 3-chloropropylmethyldipropoxysilane,3,3,3-trifluoropropylmethyldimethoxysilane,3-methacryloxypropylmethyldimethoxysilane,3-acryloxypropylmethyldimethoxysilane,3-aminopropylmethyldimethoxysilane, 3-aminopropylmethyldiethoxysilane,3-mercaptopropylmethyldimethoxysilane,3-mercaptopropylmethyldiethoxysilane,N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane or2-cyanoethylmethyldimethoxysilane.

The trialkoxy or triacyloxysilane may specifically be e.g.methyltrimethoxysilane, methyltriethoxysilane,methyltris(2-methoxyethoxy)silane, methyltriacetoxysilane,methyltripropoxysilane, methyltriisopropenoxysilane,methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane,vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane,vinyltris(2-methoxyethoxy)silane, vinyltriisopropenoxysilane,phenyltrimethoxysilane, phenyltriethoxysilane, phenyltriacetoxysilane,3-chloropropyltrimethoxysilane, 3-trifluoropropyltriethoxysilane,3-chloropropyltripropoxysilane, 3,3,3-trifluoropropyltrimethoxysilane,3-methacryloxypropyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane,3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane,3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane,N-(2-aminoethyl)-3-aminopropyltrimethoxysilane or2-cyanoethyltrimethoxysilane.

Further, the tetraalkoxysilane may specifically be e.g.tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane,tetra-n-butyloxysilane, tetra-sec-butyloxysilane ortetra-tert-butyloxysilane.

Among them, as the organooxysilane compound (c), a tetraalkoxysilanehaving a C₁₋₄ alkoxy group, or a trialkoxysilane having a C₁₋₄ alkoxygroup and a C₁₋₄ alkyl group, is preferred. Further preferred is atetraalkoxysilane such as tetramethoxysilane or tetraethoxysilane.

In the organooxysilane compound, the organooxy group is hydrolyzed toform a hydroxy group bonded to a silicon atom (a silanol group), andthen, such silanol groups undergo dehydration condensation to form asiloxane bond represented by —Si—O—Si— thereby to form a high molecularweight condensate. From a diorganooxysilane compound only, a linearpolysiloxane will be formed, but from a triorganooxysilane compound orfrom a tetraorganooxysilane compound, a three dimensional network (asilicon oxide type network) of a polysiloxane will be formed. Also froma mixture of a diorganooxysilane compound with a triorganooxysilanecompound or a tetraorganooxysilane compound, a three dimensional networkof a polysiloxane will be formed.

The coating solution for forming an ultraviolet-absorbing film of thepresent invention is one to form an ultraviolet-absorbing film havingmechanical durability such as abrasion resistance, and therefore, atleast part of the organooxysilane compounds (a) to (c) is required to bea triorganooxysilane compound or a tetraorganooxysilane compound. Amongthree types of organooxysilane compounds (a) to (c) in the presentinvention, at least the organooxysilane compound (c) is preferably atrialkoxysilane or a tetraalkoxysilane, and the organooxysilanecompounds (a) and (b) may be either a dialkoxysilane or atrialkoxysilane. In order to further increase the mechanical durabilitysuch as abrasion resistance, the organooxysilane compound (c) is morepreferably a tetraalkoxysilane. Further, both the organooxysilanecompounds (a) and (b) are preferably trialkoxysilanes.

<Partially Hydrolyzed (Co)Condensate of Organooxysilane Compound(s)>

The coating solution for forming an ultraviolet-absorbing film of thepresent invention may comprise the respective partially hydrolyzedcondensates of the organooxysilane compounds (a) to (c) as thecomponents derived respectively from the organooxysilane compounds (a)to (c). Otherwise, the coating solution for forming anultraviolet-absorbing film of the present invention may comprise apartially hydrolyzed co-condensate of optional two types among theorganooxysilane compounds (a) to (c) and the remaining one type, or maycomprise a partially hydrolyzed co-condensate of three types of theorganooxysilane compounds (a) to (c).

The partially hydrolyzed condensate is an oligomer formed by hydrolysisof the organooxysilane compounds, followed by dehydration condensation.The partially hydrolyzed condensate is usually a high molecular weightproduct of such a level that it dissolves in a solvent. The partiallyhydrolyzed condensate has organooxy groups and has such a nature that itfurther undergoes hydrolytic condensation to form a final cured product.Only from one type of organooxysilane compound, the partially hydrolyzedcondensate may be obtained, or from two or more types of organooxysilanecompounds, a partially hydrolyzed co-condensate may be obtained as theirco-condensate. For example, from a mixture of two or more epoxidizedorganooxysilane compounds, as the organooxysilane compound (a), apartially hydrolyzed co-condensate may be obtained. However, in thepresent invention, one obtainable from different types oforganooxysilane compounds among the organooxysilane compounds (a) to (c)is referred to as a partially hydrolyzed co-condensate, and oneobtainable from two or more types belonging to any one of theogranooxysilane compounds (a) to (c) will be referred to as a partiallyhydrolyzed condensate.

The partially hydrolyzed condensate may, for example, be a partiallyhydrolyzed condensate obtained from only the organooxysilane compound(a). Also from the ogranooxysilane compound (b) or the ogranooxysilanecompound (c), its partially hydrolyzed condensate can be obtained. Thepartially hydrolyzed co-condensate may, for example, be a partiallyhydrolyzed co-condensate obtainable from a mixture of an organooxysilanecompound (a) and an organooxysilane compound (b). Likewise, from amixture of an organooxysilane compound (a) and an organooxysilanecompound (c), or from a mixture of an organooxysilane compound (b) andan organooxysilane compound (c), their partially hydrolyzedco-condensate can be obtained. Further, from a mixture of three of anorganooxysilane compound (a), an organooxysilane compound (b) and anorganooxysilane compound (c), their partially hydrolyzed co-condensatecan also be obtained. Such a partially hydrolyzed condensate orpartially hydrolyzed co-condensate may contain an organooxysilanecompound as a non-reacted starting material. Hereinafter, partiallyhydrolytic condensation and partially hydrolytic co-condensation maygenerally be referred to as partially hydrolytic (co)condensation, andone thereby obtainable may be referred to as a partially hydrolyzed(co)condensate.

The partially hydrolytic (co)condensation of the above organooxysilanecompound(s) may, for example, be carried out by adding water to theorganooxysilane compound(s) as starting material(s) or an alcoholsolution thereof in the presence of an acid catalyst. The lower alcoholmay, for example, be methanol, ethanol, isopropanol or butanol. Further,as a solvent which may be used in combination with such an alcohol, aketone such as acetone or acetyl acetone, an ester such as ethyl acetateor isobutyl acetate, or an ether such as propylene glycol monomethylether, dipropylene glycol monomethyl ether or diisopropyl ether, may,for example, be mentioned. The amount of the lower alcohol to be usedfor the partially hydrolytic (co)condensation of the organooxysilanecompound(s) may specifically be an amount at a level of from 0 to 1,000parts by mass per 100 parts by mass of the organooxysilane compound(s).Further, the amount of water may specifically be an amount of preferablyfrom 4 to 20 equivalents, more preferably from 8 to 15 equivalents, bymolar ratio to the amount calculated as SiO₂, of the component derivedfrom the organooxysilane compound (c). If the amount of water is lessthan 4 equivalents by the above molar ratio, the hydrolysis may notproceed, and the haze may increase, or depending upon the substrate atthe time of coating, the coating solution may be repelled, and if itexceeds 20 equivalents, the hydrolytic rate is likely to be high, andthe storage stability for a long period of time tends to be inadequate.

Further, the above acid catalyst may specifically be e.g. an inorganicacid such as nitric acid, hydrochloric acid, sulfuric acid, phosphoricacid, phosphorous acid, perchloric acid or sulfamic acid, a carboxylicacid such as formic acid, acetic acid, propionic acid, butyric acid,glycolic acid, oxalic acid, malonic acid, succinic acid, maleic acid,phthalic acid, citric acid or malic acid, or a sulfonic acid such asmethanesulfonic acid or p-toluenesulfonic acid.

As the acid catalyst to be used for the partially-hydrolytic(co)condensation in the present invention, it is preferred to use anacid with a primary proton having a pKa (hereinafter referred to aspKa1) of from 1.0 to 5.0 with a view to letting the obtainableultraviolet-absorbing film maintain sufficient light resistance,particularly with a view to preventing deterioration by light of theultraviolet-absorbing ability. Such an acid may specifically be e.g.acetic acid (pKa1=4.76), lactic acid (pKa1=3.64), maleic acid(pKa1=1.84), malonic acid (pKa1=2.65) or oxalic acid (pKa1=1.04).

The amount of the acid to be added may be set without any particularlimitation within a range wherein the function as the catalyst can beperformed. Specifically, in a case where an acid having a pKa1 of lessthan 1 is to be used, it is preferably contained in a proportion of from0.001 to 0.1 mol/kg as the molar concentration, based on the total massof the coating solution, of the proton when the primary proton of theacid is completely dissociated, and more preferably, it is contained ina proportion of from 0.001 to 0.1 mol/kg. With a view to letting theobtainable ultraviolet-absorbing film maintain sufficient lightresistance, particularly with a view to preventing deterioration bylight of the ultraviolet-absorbing ability, in a case where an acidhaving a pKa1 of from 1.0 to 5.0 is to be used, it is preferablycontained in an amount of from 0.005 to 5.0 mol/kg, more preferably inan amount of from 0.01 to 3.5 mol/kg, as the above-mentioned molarconcentration.

Specifically, the partially hydrolytic (co)condensation of theogranooxysilane compound(s) can be carried out by stirring a reactionsolution having water added to a lower alcohol solution of theorganooxysilane compound(s) in the presence of an acid catalyst at atemperature of from 10 to 40° C. for from 1 to 48 hours.

<Composition of Coating Solution for Forming Ultraviolet-Absorbing Filmof the Present Invention>

The coating solution for forming an ultraviolet-absorbing film of thepresent invention comprises a component-derived from an epoxidizedorganooxysilane compound (a), a component derived from anorganooxysilane compound (b) (hereinafter referred to as “a silylatedbenzophenone compound”, as the case requires) which is a reactionproduct of a hydroxylated benzophenone compound and an epoxidizedorganooxysilane compound, and a component derived from anorganooxysilane compound (c) other than the above (a) and (b).

The coating solution for forming an ultraviolet-absorbing film of thepresent invention may contain, as the respective components derived fromthe organooxysilane compounds (a) to (c), the organooxysilane compounds(a) to (c) themselves, or the respective partially hydrolyzedcondensates of the organooxysilane compounds (a) to (c). Further, thecoating solution for forming an ultraviolet-absorbing film of thepresent invention may contain a partially hydrolyzed co-condensate ofoptional two types among the organooxysilane compounds (a) to (c) andthe remaining one type. Further, the coating solution for forming anultraviolet-absorbing film of the present invention may contain apartially hydrolyzed co-condensate of three types of the organooxysilanecompounds (a) to (c).

Thus, the combination of the respective components derived from theorganooxysilane compounds (a) to (c) may, for example, be a combinationof a partially hydrolyzed co-condensate of the organooxysilane compounds(a) and (c), and the organooxysilane compound (b), or a combination of apartially hydrolyzed co-condensate of the organooxysilane compounds (a)and (c), and the organooxysilane compound (b). Further, the coatingsolution for forming an ultraviolet-absorbing film of the presentinvention may contain a partially hydrolyzed co-condensate of threetypes of the organooxysilane compounds (a) to (c). Further, the coatingsolution containing the above partially hydrolyzed (co)condensate maycontain the organooxysilane compounds (a) to (c) as non-reacted startingmaterials.

In the coating solution for forming an ultraviolet-absorbing film of thepresent invention, the compositional proportion of each componentderived from the corresponding organooxysilane compound (a), (b) or (c)in the coating solution represents, in a case where the coating solutioncontains a partially hydrolyzed (co)condensate, a calculated amountobtained by calculating each constituting unit in the partiallyhydrolyzed (co)condensate to be the corresponding starting materialorganooxysilane compound (a), (b) or (c), or in a case where the coatingsolution further contains the organooxysilane compound (a), (b) or (c)in addition to such a partially hydrolyzed (co)condensate, the totalamount obtained by adding such a calculated amount and the amount ofeach corresponding organooxysilane compound (a), (b) or (c) itself. Forexample, in a case where the coating solution for forming anultraviolet-absorbing film contains only a partially hydrolyzedco-condensate of three types of the organooxysilane compounds (a) to(c), the amount of each constituting unit is calculated to be thecorresponding organooxysilane compound (a), (b) or (c) and representedby the amount of the corresponding organooxysilane compound (a), (b) or(c). Further, for example, in a case where the coating solution forforming an ultraviolet-absorbing film contains a partially hydrolyzedco-condensate of three types of the organooxysilane compounds (a) to(c), and the organooxysilane compound (c), the amount of theorganooxysilane compound (c) in the coating solution is the total amountof the constituting unit derived from the organooxysilane compound (c)in the partially hydrolyzed co-condensate and the organooxysilanecompound (c) contained as a simple substance other than theco-condensate.

In the coating solution for forming an ultraviolet-absorbing film of thepresent invention, the proportions of the components derived from theorganooxysilane compounds (a) to (c) as defined above are suchproportions that, based on 100 parts by mass of the total solid contentof the component derived from the organooxysilane compound (a), thecomponent derived from the organooxysilane compound (b) which is areaction product of a hydroxylated benzophenone compound and anepoxidized organooxysilane compound, and the component derived from theorganooxysilane compound (c) other than the above (a) and (b),preferably, the component derived from the organooxysilane compound (a)is from 5 to 50 parts by mass, the component derived from theorganooxysilane compound (b) is from 10 to 50 parts by mass, and thecomponent derived from the organooxysilane compound (c) is from 40 to 80parts by mass, more preferably, the component derived from theorganooxysilane compound (a) is from 7 to 35 parts by mass, thecomponent derived from the organooxysilane compound (b) is from 15 to 40parts by mass, and the component derived from the organooxysilanecompound (c) is from 45 to 70 parts by mass, particularly preferably,the component derived from the organooxysilane compound (a) is from 10to 30 parts by mass, the component derived from the organooxysilanecompound (b) is from 20 to 30 parts by mass, and the component derivedfrom the organooxysilane compound (c) is from 50 to 65 parts by mass.

If the proportion of the component derived from the organooxysilanecompound (a) based on 100 parts by mass of the total solid content ofthe component derived from the organooxysilane compound (a), thecomponent derived from the organooxysilane compound (b) which is areaction product of a hydroxylated benzophenone compound and anepoxidized organooxysilane compound, and the component derived from theorganooxysilane compound (c) other than the above (a) and (b), is morethan 50 parts by mass, the desired abrasion resistance may not beobtained, and if it is less than 5 parts by mass, cracking is likely tooccur when it is attempted to form a film thickness required to obtainthe desired ultraviolet-absorbing ability. If the proportion of thecomponent derived from the organooxysilane compound (b) based on 100parts by mass of the total solid content of the component derived fromthe organooxysilane compound (a), the component derived from theorganooxysilane compound (b) which is a reaction product of ahydroxylated benzophenone compound and an epoxidized organooxysilanecompound, and the component derived from the organooxysilane compound(c) other than the above (a) and (b), is more than 50 parts by mass, thedesired abrasion resistance may not be obtained, and if it is less than10 parts by mass, the desired ultraviolet ray absorbing ability may notbe obtained. If the proportion of the component derived from theorganooxysilane compound (c) based on 100 parts by mass of the totalsolid content of the component derived from the organooxysilane compound(a), the compound derived from the organooxysilane compound (b) which isa reaction product of a hydroxylated benzophenone compound and anepoxidized organooxysilane compound, and the component derived from theorganooxysilane compound (c) other than the above (a) and (b), is morethan 80 parts by mass, cracking is likely to occur when it is attemptedto form a film thickness required to obtain the desiredultraviolet-absorbing ability, and if it is less than 40 parts by mass,the desired abrasion resistance may not be obtained.

Further, in the coating solution for forming an ultraviolet-absorbingfilm of the present invention, [(a)/(b)] i.e. the content ratio of thecomponent derived from the organooxysilane compound (a) to the componentderived from the organooxysilane compound (b) is preferably from 10/90to 80/20, more preferably from 20/80 to 70/30, by mass ratio. If this(a)/(b) is smaller than 10/90, the desired abrasion resistance may notbe obtained, and if it is larger than 80/20, cracking is likely to occurwhen it is attempted to form a film thickness required to obtain thedesired ultraviolet-absorbing ability.

Further, in the coating solution for forming an ultraviolet-absorbingfilm of the present invention, [(b)/(c)] i.e. the content ratio of thecomponent derived from the organooxysilane compound (b) to the componentderived from the organooxysilane compound (c) is preferably from 20/80to 40/60, more preferably from 25/75 to 35/65, by mass ratio. If this(b)/(c) is smaller than 20/80, cracking is likely to form when it isattempted to form a film thickness required to obtain the desiredultraviolet-absorbing ability, and if it is larger than 40/60, thedesired abrasion resistance may not be obtained.

Further, in the coating solution for forming an ultraviolet-absorbingfilm of the present invention, the content of the component derived fromthe organooxysilane compound (c) is preferably from 1 to 10 mass %, morepreferably from 3 to 8 mass %, as the SiO₂ content when silicon atomscontained in this component are calculated as SiO₂. If such a totalcontent of the component derived from the organooxysilane compound (c)is less than 1%, it is required to increase the application amount ofthe coating solution in order to obtain an ultraviolet-absorbing filmhaving the desired film thickness, and consequently, the appearance islikely to deteriorate, and if it exceeds 10 mass %, the film thicknessin a state where the coating solution is applied, tends to be thick, andcracking is likely to be formed in the obtainable ultraviolet-absorbingfilm.

Further, in addition to the above organooxysilane compounds, etc. asessential components, the coating solution for forming anultraviolet-absorbing film of the present invention may contain variousoptional additives, as the case requires, within a range not to impairthe effects of the present invention.

Optional additives which may be contained in the coating solution forforming an ultraviolet-absorbing film of the present invention may, forexample, be additives to improve light resistance (hereinafter referredto as “light resistance-improving agents” as the case requires) bypreventing cracking or deterioration of the ultraviolet-absorbingability of the ultraviolet-absorbing film by irradiation with light overa long period of time.

Such light resistance-improving agents may specifically be polyepoxides,glycerin, etc., but in the present invention, polyepoxides arepreferred.

Polyepoxides are a general term for compounds having a plurality ofepoxy groups. That is, an average number of epoxy groups in polyepoxidesis at least 2, but in the present invention, a polyepoxide is preferredwherein the average number of epoxy groups is from 2 to 10.

As such polyepoxides, preferred are polyglycidyl compounds such as apollyglycidyl ether compound, a polyglycidyl ester compound and apolyglycidyl amine compound. Further, polyepoxides may either aliphaticpolyepoxides or aromatic polyepoxides, and preferred are aliphaticpolyepoxides. They are compounds having at least two epoxy groups.

Among them, a polyglycidyl ether compound is preferred, and an aliphaticpolyglycidyl ether compound is particularly preferred. The polyglycidylether compound is preferably a glycidyl ether of an at leastbifunctional alcohol, particularly preferably a glycidyl ether of an atleast trifunctional alcohol, since it is thereby possible to obtain ahigher effect to improve the light resistance. Here, such an alcohol ispreferably an aliphatic alcohol, an alicyclic alcohol or a sugaralcohol.

Specifically, ethylene glycol diglycidyl ether, polyethylene glycoldiglycidyl ether, propylene glycol diglycidyl ether, polypropyleneglycol diglycidyl ether, neopentyl glycol diglycidyl ether, glycerolpolyglycidyl ether, diglycerol polyglycidyl ether, polyglycerolpolyglycidyl ether, trimethyloipropane polyglycidyl ether, sorbitolpolyglycidyl ether, pentaerythritol polyglycidyl ether, etc. may bementioned. One of them may be used, or two or more of them may be usedin combination.

Among them, preferred is a polyglycidyl ether of an aliphatic polyolhaving at least three hydroxy groups (one wherein an average number ofglycidyl groups (epoxy groups) per one molecule exceeds 2) such asglycerol polyglycidyl ether, diglycerol polyglycidyl ether, polyglycerolpolyglycidyl ether or sorbitol polyglycidyl ether, since a higher effectto improve light resistance can be obtained.

The amount of the light resistance-improving agent to be incorporated isnot particularly limited so long as it is an amount whereby it ispossible to prevent light deterioration of the mechanical strength andultraviolet-absorbing ability of the ultraviolet-absorbing film withoutimpairing the effects of the present invention. For example, in a casewhere one member selected from polyepoxides and glycerin is to be used,its content is preferably from 0.1 to 20 parts by mass, more preferablyfrom 1.0 to 10 parts by mass, based on 100 parts by mass of the totalsolid content of the component derived from the organooxysilane compound(a), the component derived from the organooxysilane compound (b) whichis a reaction product of a hydroxylated benzophenone compound and anepoxidized organooxysilane compound, and the component derived from theorganooxysilane compound (c) other than the above (a) and (b) in thecoating solution for an ultraviolet-absorbing film. If the amount of thelight-resistance-improving agent is less than 0.1 part by mass, theremay be a case where light deterioration of the ultraviolet-absorbingability cannot be sufficiently prevented, and if it exceeds 20 parts byweight, the mechanical strength of the ultraviolet-absorbing film islikely to deteriorate.

The coating solution for forming an ultraviolet-absorbing film of thepresent invention may further contain a light stabilizer for the purposeof improving the light resistance. As such a light stabilizer, ahindered amine type light stabilizer (HALS) may, for example, bepreferably mentioned. The amount of the light stabilizer to beincorporated is preferably from 0.01 to 0.015 part by mass, morepreferably from 0.002 to 0.009 part by mass per 100 parts by mass of thetotal solid content of the component derived from the organooxysilanecompound (a), the component derived from the organooxysilane compound(b) which is a reaction product of a hydroxylated benzophenone compoundand an epoxidized organooxysilane compound, and the component derivedfrom the organooxysilane compound (c) other than the above (a) and (b).

An optional additive which the coating solution for forming anultraviolet-absorbing film of the present invention may contain, mayfurther be fine silica particles to be incorporated to further improvethe abrasion resistance of the ultraviolet-absorbing film. The finesilica particles are preferably incorporated in the form of colloidalsilica, when they are incorporated to the coating solution for formingan ultraviolet-absorbing film. Here, the colloidal silica is one havingfine silica particles dispersed in water or an organic solvent such asmethanol, ethanol, isobutanol or propylene glycol monomethyl ether. Atthe time of preparing the coating solution for formingultraviolet-absorbing film of the present invention, the colloidalsilica may be suitably incorporated to obtain a coating solution forforming an ultraviolet-absorbing film containing fine silica particles.Further, in a case where a partially hydrolyzed (co)condensate of anorganooxysilane compound is to be produced, the colloidal silica may beincorporated to the starting material organooxysilane compound, followedby partial hydrolytic (co)condensation to obtain a partially hydrolyzed(co)condensate containing fine silica particles, which may be used toprepare the coating solution for forming an ultraviolet-absorbing filmof the present invention containing fine silica particles.

In a case where fine silica particles are to be incorporated as anoptional component to the coating solution for an ultraviolet-absorbingfilm of the present invention, it is preferred to incorporate finesilica particles having an average particle size (BET method) of from 1to 100 nm. If the average particle size exceeds 100 nm, the particlestend to diffusely reflect light, whereby the haze value of theobtainable ultraviolet-absorbing film tends to be large, such beingundesirable from the viewpoint of the optical quality. Further, theaverage particle size is particularly preferably from 5 to 40 nm,whereby it is possible to maintain the transparency of theultraviolet-absorbing film, while imparting abrasion resistance to theultraviolet-absorbing film. Further, the colloidal silica may be used inthe form of either a water-dispersion type or an organic solventdispersion type, but it is preferred to use an organicsolvent-dispersion type. In the case of using a water-dispersion type,it is preferred to use colloidal silica dispersed in an acidic aqueoussolution. Further, to the colloidal silica, fine inorganic particlesother than fine silica particles, such as alumina sol, titania sol orceria sol, may be incorporated.

Further, in a case where fine silica particles are to be incorporated asan optional component to the coating solution for forming anultraviolet-absorbing film of the present invention, their amount to beincorporated is preferably from 0.5 to 50 parts by mass, more preferablyfrom 10 to 30 parts by mass, per 100 parts by mass of the total solidcontent of the component derived from the organooxysilane compound (a),the component derived from the organooxysilane compound (b) which is areaction product of a hydroxylated benzophenone compound and anepoxidized organooxysilane compound, and the component derived from theorganooxysilane compound (c) other than the above (a) and (b). The aboverange is the range of fine silica particles to be incorporated whereinit is possible to maintain the film-forming property of theultraviolet-absorbing film, while securing sufficient abrasionresistance, and it is possible to prevent cracking or deterioration ofthe transparency of the ultraviolet-absorbing film by agglomeration offine silica particles one another.

The coating solution for forming an ultraviolet-absorbing film of thepresent invention may further contain functional fine particles such asindium tin oxide fine particles or antimony tin oxide fine particles, oran organic dye for the purpose of imparting functionality.

Further, for the purpose of the coating property on a substrate andsmoothness of the coating film thereby obtainable, a surface activeagent may be incorporated as an additive.

The coating solution for forming an ultraviolet-absorbing film of thepresent invention may further contain additives such as a defoamingagent, a viscosity-controlling agent, etc. for the purpose of improvingthe coating property on a substrate, or contain additives such as anadhesion-imparting agent, etc. for the purpose of improving the adhesionto the substrate. The amount of each of such additives is preferablyfrom 0.01 to 2 parts by mass, per 100 parts by mass of the total solidcontent of the component derived from organooxysilane compound (a), thecompound derived from organooxysilane compound (b) which is a reactionproduct of a hydroxylated benzophenone compound and an epoxidizedorganooxysilane compound, and the component derived from theorganooxysilane compound (c) other than the above (a) and (b). Further,the coating solution for forming an ultraviolet-absorbing film of thepresent invention may contain a dye, a pigment, a filler, etc. within arange not to impair the purpose of the present invention.

Further, an additive to impart flexibility to the ultraviolet-absorbingfilm may, for example, be mentioned as an optional additive which thecoating solution for forming an ultraviolet-absorbing film of thepresent invention may contain.

The additive to impart flexibility may, for example, be various organicresins, such as a silicone resin, an acrylic resin, a polyvinyl butyral(PVB) resin, a polyester resin, a polyurethane resin, an epoxy resin,etc.

By the coating solution for forming an ultraviolet-absorbing film of thepresent invention, an ultraviolet-absorbing film is formed by curing, asdescribed hereinafter, the curable components, such as the componentderived from the organooxysilane compound (a), the component derivedfrom the organooxysilane compound (b) and the component derived from theorganooxysilane compound (c), contained in the coating solution. Thecoating solution for forming an ultraviolet-absorbing film of thepresent invention preferably contains an acid catalyst to accelerate thecuring.

Specifically, the acid catalyst may, for example, be an inorganic acidsuch as nitric acid, hydrochloric acid, sulfuric acid, phosphoric acid,phosphorous acid, perchloric acid or sulfamic acid, a carboxylic acidsuch as formic acid, acetic acid, propionic acid, butyric acid, glycolicacid, oxalic acid, malonic acid, succinic acid, maleic acid, phthalicacid, citric acid or malic acid, or a sulfonic acid such asmethanesulfonic acid or p-toluenesulfonic acid.

In the present invention, among them, it is preferred to employ an acidhaving a primary proton pKa of from 1.0 to 5.0 with a view to lettingthe obtainable ultraviolet-absorbing film maintain sufficientlight-resistance, particularly with a view to preventing lightdeterioration of the ultraviolet-absorbing ability. Specifically, suchan acid may, for example, be acetic acid (pKa1=4.76), lactic acid(pKa1=3.64), maleic acid (pKa1=1.84), malonic acid (pKa1=2.65) or oxalicacid (pKa1=1.04).

Further, in the coating solution for forming an ultraviolet-absorbingfilm of the present invention, with a view to improving lightresistance, particularly preventing light deterioration of theultraviolet-absorbing ability, it is preferred to use an acid having aprimary proton pKa of from 1.0 to 5.0 together with the above-mentionedlight resistance-improving agent such as a polyepoxide or glycerin.

The amount of the acid to be incorporated may be set without anyparticular limitation, within a range where the function as a catalystcan be performed, but specifically, in a case where an acid having apKa1 of less than 1.0 is to be used, such an acid is incorporatedpreferably in a proportion of from 0.001 to 0.1 mol/kg, more preferablyfrom 0.001 to 0.01 mol/kg, as the molar concentration, based on thetotal mass of the coating solution, of the proton when the primaryproton of the acid is completely dissociated. If concentration of theacid to be used is less than 0.001 mol/kg, no adequate function as thecatalyst may be performed, and if it exceeds 0.1 mol/kg, theultraviolet-absorbing film is likely to undergo yellowing.

Particularly, with a view to letting the obtainableultraviolet-absorbing film maintain sufficient light resistance andpreventing light deterioration of the ultraviolet-absorbing ability, itis preferred to employ an acid having a pKa1 of from 1.0 to 5.0. In sucha case, the acid is incorporated in a proportion of preferably from0.005 to 5.0 mol/kg, more preferably from 0.01 to 3.5 mol/kg, as theabove mentioned molar concentration. If the concentration of the acid tobe used is less than 0.005 mol/kg, the hydrolysis may not proceed, thehaze tends to increase during the film formation or depending upon thesubstrate, the coating solution may be repelled, and if it exceeds 5.0mol/kg, the hydrolysis rate tends to increase, whereby the storagestability for a long period of time is likely to be inadequate.

The coating solution for forming an ultraviolet-absorbing film of thepresent invention may contain a curing catalyst in addition to the aboveacid catalyst. Such a curing catalyst may, for example, be an alkalimetal salt such as a lithium salt, sodium salt or potassium salt, of analiphatic carboxylic acid such as formic acid, acetic acid, propionicacid, butyric acid, lactic acid, tartaric acid or succinic acid; aquaternary ammonium salt such as a benzyltrimethylammonium salt, atetramethylammonium salt or a tetraethylammonium salt; a metal alkoxideor chelate of e.g. aluminum, titanium or cerium; ammonium perchlorate,ammonium chloride, ammonium sulfate, sodium acetate, an imidazole or itssalt, ammonium trifluoromethylsulfonate, orbis(trifluoromethylsulfonyl)bromomethyl ammonium.

Further, in the present invention, in order to obtain the desiredabrasion resistance, it is preferred to adjust the pH of the coatingsolution for forming an ultraviolet-absorbing film to be from 1.0 to5.0, more preferably from 2.0 to 4.5. As a method for adjusting the pH,a method of adjusting the content of the acid catalyst or the content ofthe curing catalyst, within the above-mentioned preferred range, may bementioned.

The coating solution for forming an ultraviolet-absorbing film of thepresent invention usually contains water to subject the organooxysilanecompounds, etc. to hydrolysis/condensation polymerization, in additionto the prescribed amounts of the above mentioned organooxysilanecompounds, etc. as the essential components and various additives, etc.as optional additives.

The amount of water to be contained in the coating solution for formingan ultraviolet-absorbing film of the present invention is notparticularly limited so long as it is a sufficient amount to subject theorganooxysilane compounds, etc. to hydrolysis/condensationpolymerization, but it is preferably from 4 to 20 equivalents, morepreferably from 8 to 15 equivalents, by molar ratio to the amount,calculated as SiO₂, of the component derived from the organooxysilanecompound (c). If the amount of water is less than 4 equivalents by theabove molar ratio, the hydrolysis tends not to proceed, the haze islikely to increase during the film forming, or depending upon thesubstrate, the coating solution is likely to be repelled at the time ofcoating, and if it exceeds 20 equivalents, the hydrolysis rate tends toincrease, whereby the storage stability for a long period of time islikely to be inadequate.

An ultraviolet-absorbing film to be formed by using the coating solutionfor forming an ultraviolet-absorbing film of the present inventionusually has sufficient hardness durable in usual use. However, in a casewhere an acid having a pKa1 of from 1.0 to 5.0 is used as an acidcatalyst for the coating solution for forming an ultraviolet-absorbingfilm for the purpose of improving the light resistance of the obtainableultraviolet-absorbing film, particularly for the purpose of preventinglight deterioration of the ultraviolet-absorbing ability, deteriorationof the hardness, e.g. deterioration of the scratching resistance, maysometimes be observed. In order to prevent such deterioration of thescratching resistance thereby to maintain the hardness of theultraviolet-absorbing film at a constant level, in the coating solutionfor forming an ultraviolet-absorbing film of the present invention, itis preferred to incorporate fine silica particles and further increasethe amount of water to be incorporated to subject the organooxysilanecompounds, etc. to hydrolysis/condensation polymerization, particularlywhen an acid having a pKa1 of from 1.0 to 5.0 is employed. The finesilica particles to be used here may be the same fine silica particlesas described above. A preferred embodiment may be the same.

With respect to the amounts of the fine silica particles and water,specifically, the fine silica particles are incorporated in an amount ofpreferably from 0.5 to 50 parts by mass, more preferably from 1.0 to 10parts by mass, per 100 parts by mass of the total solid content of thecomponent derived from the organooxysilane compound (a), the componentderived from the organooxysilane compound (b) which is a reactionproduct of a hydroxylated benzophenone compound and an epoxidizedorganooxysilane compound, and the component derived from theorganooxysilane compound (c) other than the above (a) and (b), and thewater is incorporated in an amount of preferably from 8 to 20equivalents, more preferably from 12.5 to 17.5 equivalents, by molarratio to the amount, calculated as SiO₂, of the component derived fromthe organooxysilane compound (c).

Here, in a case where a water dispersion type colloidal silica is usedas the fine silica particles, such water is also regarded as the watercontained in the coating solution for forming an ultraviolet-absorbingfilm.

If either one of the amounts of fine silica particles and water, issmaller than the lower limit of the corresponding amount, the scratchingresistance is likely to deteriorate. Further, if fine silica particlesare incorporated beyond the above upper limit, the film forming propertyfor the ultraviolet-absorbing film may be adversely influenced, and ifwater is incorporated beyond the above upper limit, the hydrolysis ratetends to increase, whereby the storage stability for a long period oftime is likely to be inadequate.

The coating solution for forming an ultraviolet-absorbing film of thepresent invention is prepared usually in such a form that the prescribedamounts of the organooxysilane compounds, etc., as the essentialcomponents, and optional amounts of various additives, etc. as optionaladditives, are dissolved or dispersed in a solvent. It is necessary thatall non-volatile components in the coating solution for forming anultraviolet-absorbing film are stably dissolved or dispersed, and forsuch a purpose, the solvent contains at least 20 mass %, preferably atleast 50 mass %, of an alcohol.

As the alcohol to be used for such a solvent, methanol, ethanol,1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol,1-methoxy-2-propanol, 2-ethoxyethanol, 4-methyl-2-pentanol,2-butoxyethanol, etc. are preferred, and among them, an alcohol having aboiling point of from 80 to 160° C. is preferred from such a viewpointthat the solubility of the component derived from the organooxysilanecompound (a), the component derived from the organooxysilane compound(b) which is a reaction product of a hydroxylated benzophenone compoundand an epoxidized organooxysilane compound, and the component derivedfrom the organooxysilane compound (c) other than the above (a) and (b)is good, and the coating property on a substrate is good. Specifically,ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol,2-methyl-1-propanol, 1-methoxy-2-propanol, 2-ethoxyethanol,4-methyl-2-pentanol or 2-butoxyethanol is preferred.

Further, in the coating solution forming an ultraviolet-absorbing filmof the present invention, as a solvent other than those described above,a solvent other than an alcohol, which is miscible with water/alcohol,may be used in combination, and such a solvent may, for example, be aketone such as acetone or acetylacetone; an ester such as ethyl acetateor isobutyl acetate; or an ether such as propylene glycol monomethylether, dipropylene glycol monomethyl ether or diisopropyl ether.

The amount of the solvent to be used in the coating solution for formingan ultraviolet-absorbing film of the present invention is preferablyfrom 100 to 1,900 parts by mass, more preferably from 250 to 900 partsby mass per 100 parts by mass of all no-volatile components in thecoating solution for forming an ultraviolet-absorbing film.

Further, in a case where the coating solution for forming anultraviolet-absorbing film of the present invention contains theogranooxysilane compounds (a) to (c) themselves as the componentsderived respectively from the organooxysilane compounds (a) to (c), theymay be subjected to treatment for partially hydrolytic (co)condensationto stabilize the coating solution for e.g. storage. Usually, thispurpose can be accomplished by stirring for a predetermined time at roomtemperature in the presence of an acid catalyst after mixing theorganooxysilane compounds (a) to (c).

[Ultraviolet-Absorbing Glass Article of the Present Invention]

The ultraviolet-absorbing glass article of the present inventioncomprises a glass substrate and an ultraviolet-absorbing film formed onat least part of the glass substrate surface by using the coatingsolution for forming an ultraviolet-absorbing film of the presentinvention.

The material for the glass substrate to be used for theultraviolet-absorbing glass article of the present invention is notparticularly limited and may, for example, be usual soda lime glass,borosilicate glass, alkali free glass or quartz glass. Further, as theglass substrate for the ultraviolet-absorbing glass article of thepresent invention, it is possible to use a glass substrate which absorbsultraviolet rays or infrared rays.

Further, the ultraviolet-absorbing glass article of the presentinvention is preferably applied to an application where abrasionresistance is particularly required. Specifically, it is useful for awindow of an automobile, particularly for a window shield or for asliding window.

The ultraviolet-absorbing glass article of the present invention has anultraviolet-absorbing film formed as described later by using thecoating solution for forming an ultraviolet-absorbing film of thepresent invention having the above-described construction and makes itpossible that the transmittance of light having a wavelength of 380 nmas measured by using a spectrophotometer (U-3500, manufactured byHitachi, Ltd.) is at most 7.0%, preferably at most 4.0%, more preferablyat most 1.0%, by the ultraviolet-absorbing ability of the hydroxylatedbenzophenone compound residue, which the component derived from theorganooxysilane compound (b) has.

Further, a hydroxylated benzophenone compound residue as anultraviolet-absorbing component is fixed to a silicon oxide networkconstituting the ultraviolet-absorbing film and is less susceptible tobleeding out in use for a long period of time, and thus, it makes theultraviolet-absorbing glass article of the present invention to beexcellent in long-term storage stability of the ultraviolet-absorbingability. Further, in the ultraviolet-absorbing glass article of thepresent invention, the component derived from the organooxysilanecompound (a) and the component derived from the organooxysilane compound(c) function as a binder component to form the silicon oxide typenetwork having the component derived from the organooxysilane compound(b) fixed thereto, whereby it becomes possible to satisfy the adhesionof the ultraviolet-absorbing film to the glass substrate, the hardnesssuch as the scratching resistance and the cracking resistance at a highdimensional level.

Further, the ultraviolet-absorbing film formed by using the coatingsolution for forming an ultraviolet-absorbing film wherein a lightresistance-improving agent such as the above mentioned polyepoxide orglycerin is incorporated, and/or the above-mentioned acid having a pKa1of from 1.0 to 5.0 is used as an acid catalyst, preferably both of themare contained, is an ultraviolet-absorbing film having light resistancei.e. durability against irradiation with light over a long period oftime, whereby light deterioration of the mechanical strength and theultraviolet-absorbing ability of the ultraviolet-absorbing film isprevented.

The ultraviolet-absorbing glass article of the present invention has anultraviolet-absorbing film containing, as the main constituting element,a silicon oxide type network formed from the coating solution forforming an ultraviolet-absorbing film of the present invention, wherebyit becomes possible that when an abrasion test of 1,000-rotations with aCS-10F abrasive wheel is applied against the surface of theultraviolet-absorbing film in accordance with JIS-R3212 (1998), theincrease in the haze after the test as compared to before the test ismade to be at most 5.0%.

A specific process for applying the coating solution for forming anultraviolet-absorbing film of the present invention on theabove-mentioned glass substrate, may, for example, be a process whichcomprises (A) a step of applying the coating solution on the glasssubstrate to form a coating film and (B) a step of removing the organicsolvent from the coating film and curing the three components derivedrespectively from the organooxysilane compounds (a) to (c) (hereinafterreferred to as “organooxysilane compounds”) to form a cured productthereby to form an ultraviolet-absorbing film.

The coating solution is applied on the glass substrate to form a coatingfilm of the coating solution. The coating film to be formed here is acoating film containing the above solvent. The method for applying thecoating solution on the glass substrate is not particularly limited solong as it is a method capable of uniformly applying the coatingsolution. A known method may be used such as a flow coating method, adip coating method, a spin coating method, a spray coating method, aflexoprinting method, a screen printing method, a gravure printingmethod, a roll coating method, a meniscus coating method or a diecoating method. The thickness of the coating film of the coatingsolution is determined taking into consideration the thickness of thefinally obtainable ultraviolet-absorbing film.

Then, the step (B) of removing the solvent from the coating film of thecoating solution on the glass substrate and curing the organooxysilanecompounds to form an ultraviolet-absorbing film, is carried out.

The above coating film of the coating solution contains the volatileorganic solvent, etc., and therefore, after forming the coating film bythe coating-solution, firstly, such a volatile component is evaporatedand removed. Such removal of the volatile component is carried outpreferably by heating and/or drying under reduced pressure. With a viewto improving the leveling property of the coating film, it is preferredto carry out temporarily drying at a temperature of from about roomtemperature to 120° C. after forming the coating film of the coatingsolution on the glass substrate. Usually, during this temporary drying,the volatile component is vaporized and removed, and therefore, theoperation for removal of the volatile component is included in thetemporary drying. The time for the temporary drying i.e. the time forthe operation of removing the volatile component is preferably fromabout 3 seconds to 2 hours, although it depends also on the coatingsolution to be used for forming the coating film.

At that time, it is preferred that the volatile component issufficiently removed, but it may not completely be removed. That is, theorganic solvent, etc. may remain in the ultraviolet-absorbing filmwithin a range not influence the performance of theultraviolet-absorbing film. Further, in a case where heating is carriedout to remove the above volatile component, heating to prepare a siliconoxide type compound which may subsequently be carried out as the caserequires, and heating to remove the above volatile component i.e.temporary drying, may be continuously carried out.

After removing the volatile component from the coating film as describedabove, the organooxysilane compounds are cured. This reaction can becarried out at room temperature or under heating. In a case where acured product (the silicon oxide type network) is formed under heating,the upper limit of the heating temperature is preferably 200° C.,particularly preferably 190° C., since the cured product contains anorganic component. The cured product can be formed even at roomtemperature, and therefore, the lower limit of the heating temperatureis not particularly limited. However, in a case where acceleration ofthe reaction by heating is intended, the lower limit of the heatingtemperature is preferably 60° C., more preferably 80° C. Therefore, thisheating temperature is preferably from 60 to 200° C., more preferablyfrom 80 to 190° C. The heating time is preferably from a few minutes toa few hours, although it may depend also on the coating solution to beused for forming the coating film.

The thickness of the ultraviolet-absorbing film in theultraviolet-absorbing glass article having the ultraviolet-absorbingfilm thus formed by using the coating solution for forming anultraviolet-absorbing film of the present invention, is preferably from1.0 to 8.0 μm, more preferably from 1.5 to 7.0 μm. If the thickness ofthe ultraviolet-absorbing film is less than 1.0 μm, theultraviolet-absorbing effects are likely to be inadequate. Further, ifthe thickness of the ultraviolet-absorbing film exceeds 8.0 μm, crackingis likely to result when the desired abrasion resistances attained.

EXAMPLES

Now, the present invention will be described in further detail withreference to Examples, but it should be understood that the presentinvention is by no means restricted to such Examples. The followingExamples 1 to 18 are working examples of the present invention, andExamples 19 to 21 are comparative examples. Further, constitutingcompounds of reagents represented by tradenames in Examples are asfollows.

<Resin>

SR-SEP: sorbitol type polyglycidyl ether, manufactured by SAKAMOTOYAKUHIN KOGYO CO., LTD.

<Others>

SOLMIX AP-a: a mixed solvent of ethano:isopropylalcohol:methanol=85:10:5 (mass ratio), manufactured by Japan AlcoholTrading CO., LTD.

Methanol silica sol: colloidal silica having fine silica particleshaving an average primary particle size of from 10 to 20 nm dispersed inmethanol at a solid content concentration of 30 mass %, manufactured byNissan Chemical Industries, Ltd.

Preparation Example for Silylated Ultraviolet-Absorber

49.2 g of 2,2′,4,4′-tetrahydroxybenzophenone (manufactured by BASF),47.3 g of 3-glycidoxypropyltrimethoxysilane (manufactured by Shin-EtsuChemical Co., Ltd.), 0.8 g of benzyltriethylammonium chloride(manufactured by Junsei Chemical Co., Ltd.) and 100 g of butyl acetate(manufactured by Junsei Chemical Co., Ltd.) were charged, heated to 60°C. with stirring and dissolved and then heated to 120° C. and reactedfor 4 hours to obtain a silylated ultraviolet-absorber solution having asolid content concentration of 49 mass %.

Example 1

41.9 g of ethanol, 17.3 g of tetramethoxysilane, 5.8 g of3-glycidoxypropyltrimethoxysilane, 15.0 g of the silylated ultravioletabsorber-solution obtained in the above Preparation Example, 15.8 g ofpure water and 4.2 g of 1% nitric acid aqueous solution were charged andstirred for one hour to obtain a coating solution 1 for forming anultraviolet-absorbing film. Then, the coating solution 1 was applied bya spin coating method on a high heat-absorbing green glass having itssurface cleaned (Tv: 75.2%, Tuv: 9.5%, transmittance of light with awavelength of 380 nm: 38.5%, 10 cm in length, 10 cm in width, 3.5 cm inthickness, tradename: UVFL, manufactured by Asahi Glass Company,Limited) and dried in atmospheric air at 150° C. for 30 minutes, toobtain an ultraviolet-absorbing film-attached glass plate. Theproperties of the obtained ultraviolet-absorbing film-attached glassplate were evaluated as follows. The evaluation results are shown inTable 2.

[Evaluations]

1) Film thickness: Cross sectional observation of theultraviolet-absorbing film was carried out by a scanning electronmicroscope (S-800, manufactured by Hitachi, Ltd.), and the filmthickness [nm] was obtained from the obtained observation image.

2) Crack: The ultraviolet-absorbing film after drying was observedvisually and by a metal microscope, and whether or not a crack wasformed on the layer surface, was judged. One wherein no crack was formedi.e. no crack was observed visually or by the microscope, was evaluatedto be ◯, one wherein a crack was not observed visually but observed bythe microscope was evaluated to be Δ, and one wherein a crack wasobserved even visually was evaluated to be x.

3) The spectral properties were judged by the transmittance of light ata wavelength of 380 nm as measured by means of a spectrophotometer(U-3500 manufactured by Hitachi Ltd.), and by the visible lighttransmittance and the ultraviolet transmittance calculated in accordancewith JIS-R3106.

4) Abrasion resistance: Using Taber's abrasion resistance test machine,in accordance with the method disclosed in JIS-R3212 (1998), an abrasiontest of 1,000 rotations with a CS-10F abrasive wheel was carried out,whereby the degrees of scar before and after the test were measured byhaze values, and the abrasion resistance was evaluated by an increase[%] in the haze value.

5) Moisture resistance test: A sample was put in a constant temperatureconstant humidity tank at 80° C. with a relative humidity of 95%, andupon expiration of 1,000-hours, the transmittance of light at awavelength of 380 nm through the sample was measured, and at the sametime, judgment of a crack was carried out by the same method as in theabove 2).

6) Accelerated weather resistance test (evaluation of light resistance):A sample was set in a Super Xenon Weather Meter (SX75 manufactured bySuga Test Instruments Co., Ltd.), and the sample was exposed underconditions of an illumination intensity of 150 W/m² (300 to 400 nm), ablack panel temperature of 83° C. and a relative humidity of 50%, andupon expiration of 1,000 hours, the transmittance of light at awavelength of 380 nm through the sample was measured, and at the sametime, judgment of a crack was carried out in the same manner as in theabove 2).

7) Scratch test (scratching resistance/hardness evaluation): On theultraviolet ray-absorbing film on the glass plate, a ball point pen waspressed manually, and the surface was scratched for 2 cm, whereupon thescratch mark was visually judged for the scratch test. The film having ascratch mark visually observed was evaluated to be x, and one having noor substantially no scratch mark visually observed was evaluated to be◯.

Example 2

An ultraviolet ray-absorbing film-attached glass plate was prepared inthe same manner as in Example 1 except that the film thickness waschanged. The properties of the obtained ultraviolet-absorbingfilm-attached glass plate were evaluated in the same manner as inExample 1. The evaluation results are shown in Table 2.

Example 3

42.6 g of ethanol, 18.1 g of tetramethoxysilane, 4.6 g of3-glycidoxypropyltrimethoxysilane, 14.8 g of the silylated ultravioletabsorber solution obtained in the above Preparation Example, 15.8 g ofpure water and 4.2 g of a 1% nitric acid aqueous solution were chargedand stirred for one hour to obtain a coating solution 2 for forming anultraviolet-absorbing film. An ultraviolet-absorbing film-attached glassplate was prepared in the same manner as in Example 1 except that theabove coating solution 2 was used instead of the coating solution 1. Theproperties of the obtained ultraviolet-absorbing film-attached glassplate were evaluated in the same manner as in Example 1. The evaluationresults are shown in Table 2.

Example 4

41.9 g of ethanol, 15.4 g of tetramethoxysilane, 8.0 g of3-glycidoxypropyltrimethoxysilane, 15.2 g of the silylated ultravioletabsorber solution obtained in the above Preparation Example, 15.4 g ofpure water and 4.2 g of a 1% nitric acid aqueous solution were chargedand stirred for one hour to obtain a coating solution 3 for forming anultraviolet-absorbing film. An ultraviolet-absorbing film-attached glassplate was prepared in the same manner as in Example 1 except that theabove coating solution 3 was used instead of the coating solution 1. Theproperties of the obtained ultraviolet-absorbing film-attached glassplate were evaluated in the same manner as in Example 1. The evaluationresults are shown in Table 2.

Example 5

46.2 g of ethanol, 16.6 g of tetramethoxysilane, 2.8 g of3-glycidoxypropyltrimethoxysilane, 17.0 g of the silylated ultravioletabsorber solution obtained in the above Preparation Example, 13.8 g ofpure water and 3.6 g of a 1% nitric acid aqueous solution were chargedand stirred for one hour to obtain a coating solution 4 for forming anultraviolet-absorbing film. An ultraviolet-absorbing film-attached glassplate was prepared in the same manner as in Example 1 except that theabove coating solution 4 was used instead of the coating solution 1. Theproperties of the obtained ultraviolet-absorbing film-attached glassplate were evaluated in the same manner as in Example 1. The evaluationresults are shown in Table 2.

Example 6

38.8 g of ethanol, 16.4 g of tetramethoxysilane, 9.8 g of3-glycidoxypropyltrimethoxysilane, 13.4 g of the silylated ultravioletabsorber solution obtained in the above Preparation Example, 17.1 g ofpure water and 4.5 g of a 1% nitric acid aqueous solution were chargedand stirred for one hour to obtain a coating solution 5 for forming anultraviolet-absorbing film. An ultraviolet-absorbing film-attached glassplate was prepared in the same manner as in Example 1 except that theabove coating solution 5 was used instead of the coating solution 1. Theproperties of the obtained ultraviolet-absorbing film-attached glassplate were evaluated in the same manner as in Example 1. The evaluationresults are shown in Table 2.

Example 7

21.2 g of SOLMIX AP-1, 15.0 g of tetramethoxysilane, 5.1 g of3-glycidoxypropyltrimethoxysilane, 14.6 g of the silylated ultravioletabsorber solution obtained in the above Preparation Example, 1.2 g ofSR-SEP as polyepoxide, 2.1 g of methanol silica sol as colloidal silica,14.2 g of acetic acid and 26.6 g of ion-exchanged water were charged andstirred for one hour. Then, 4.94 g of SOLMIX AP-1 was added and stirredto obtain a coating solution 6 for forming an ultraviolet-absorbingfilm. An ultraviolet-absorbing film-attached glass plate was prepared inthe same manner as in Example 1 except that the above coating solution 6was used instead of the coating solution 1 and the drying conditionswere changed to 180° C. for 30 minutes. The properties of the obtainedultraviolet-absorbing film-attached glass plate were evaluated in thesame manner as in Example 1 except that the temperature for the moistureresistance test was changed to 50° C. The evaluation results are shownin Table 2.

Example 8

An ultraviolet-absorbing film-attached glass plate was prepared in thesame manner as in Example 7 except that the film thickness was changed.The properties of the obtained ultraviolet-absorbing film-attached glassplate was evaluated in the same manner as in example 7. The evaluationresults are shown in Table 2.

Example 9

14.0 g of SOLMIX AP-1, 16.5 g of tetramethoxysilane, 5.2 g of3-glycidoxypropyltrimethoxysilane, 15.0 g of the silylated ultravioletabsorber solution obtained in the above Preparation Example, 0.3 g ofSR-SEP as polyepoxide, 4.2 g of methanol silica sol as colloidal silica,15.6 g of acetic acid and 29.2 g of ion-exchanged water were charged andstirred for one hour. Then, 4.94 g of SOLMIX AP-1 was added and stirredto obtain a coating solution 7 for forming an ultraviolet-absorbingfilm. An ultraviolet-absorbing film-attached glass plate was prepared inthe same manner as in Example 7 except that the above coating solution 7was used instead of the coating solution 6. The properties of theobtained ultraviolet-absorbing film-attached glass plate were evaluatedin the same manner as in Example 7. The evaluation results are shown inTable 2.

Example 10

20.5 g of SOLMIX AP-1, 14.5 g of tetramethoxysilane, 5.3 g of3-glycidoxypropyltrimethoxysilane, 15.0 g of the silylated ultravioletabsorber solution obtained in the above Preparation Example, 1.1 g ofSR-SEP as polyepoxide, 4-2 g of methanol silica sol as colloidal silica,13.7 g of acetic acid and 25.7 g of ion-exchanged water were charged andstirred for one-hour. Then, 4.94 g of SOLMIX AP-1 was added and stirredto obtain a coating solution 8 for forming an ultraviolet-absorbingfilm. An ultraviolet-absorbing film-attached glass plate was prepared inthe same manner as in Example 7 except that the above coating solution 8was used instead of the coating solution 6. The properties of theobtained ultraviolet-absorbing film-attached glass plate were evaluatedin the same manner as in Example 7. The evaluation results are shown inTable 2.

Example 11

49.5 g of SOLMIX AP-1, 15.5 g of tetramethoxysilane, 4.9 g of3-glycidoxypropyltrimethoxysilane, 14.1 g of the silylated ultravioletabsorber solution obtained in the above Preparation Example, 1.3 g ofSR-SEP as polyepoxide, 3.1 g of a 1% nitric acid aqueous solution and11.6 g of ion-exchanged water were charged and stirred for one hour.Then, 4.94 g of SOLMIX AP-1 was added and stirred to obtain a coatingsolution 9 for forming an ultraviolet-absorbing film. Anultraviolet-absorbing film-attached glass plate was prepared in the samemanner as in Example 7 except that the above coating solution 9 was usedinstead of the coating solution 6. The properties of the obtainedultraviolet-absorbing film-attached glass plate were evaluated in thesame manner as in Example 7. The evaluation results are shown in Table2.

Example 12

34.9 g of SOLMIX AP-1, 15.5 g of tetramethoxysilane, 4.9 g of3-glycidoxypropyltrimethoxysilane, 14.1 g of the silylated ultravioletabsorber solution obtained in the above Preparation Example, 1.3 g ofSR-SEP as polyepoxide, 14.6 g of acetic acid and 14.6 g of ion-exchangedwater were charged and stirred for one hour. Then, 4.94 g of SOLMIX AP-1was added and stirred to obtain a coating solution 10 for forming anultraviolet-absorbing film. An ultraviolet-absorbing film-attached glassplate was prepared in the same manner as in Example 7 except that theabove coating solution 10 was used instead of the coating solution 6.The properties of the obtained ultraviolet-absorbing film-attached glassplate were evaluated in the same manner as in Example 7. The evaluationresults are shown in Table 2.

Example 13

33.9 g of SOLMIX AP-1, 15.8 g of tetramethoxysilane, 5.0 g of3-glycidoxypropyltrimethoxysilane, 14.4 g of the silylated ultravioletabsorber solution obtained in the above Preparation Example, 1.0 g ofglycerin (manufactured by Junsei Chemical Co., Ltd.), 14.9 g of aceticacid and 14.9 g of ion-exchanged water were charged and stirred for onehour. Then, 4.94 g of SOLMIX AP-1 was added and stirred to obtain acoating solution 11 for forming an ultraviolet-absorbing film. Anultraviolet-absorbing film-attached glass plate was prepared in the samemanner as in Example 7 except that the above coating solution 11 wasused instead of the coating solution 6. The properties of the obtainedultraviolet-absorbing film-attached glass plate were evaluated in thesame manner as in Example 7. The evaluation results are shown in Table2.

Example 14

50.3 g of SOLMIX AP-1, 12.1 g of tetramethoxysilane, 3.8 g of3-glycidoxypropyltrimethoxysilane, 11.0 g of the silylated ultravioletabsorber solution obtained in the above Preparation Example, 11.4 g ofacetic acid and 11.4 g of ion-exchanged water were charged and stirredfor one hour. Then, 4.94 g of SOLMIX AP-1 was added and stirred toobtain a coating solution 12 for forming an ultraviolet-absorbing film.An ultraviolet-absorbing film-attached glass plate was prepared in thesame manner as in Example 7 except that the above coating solution 12was used instead of the coating solution 6. The properties of theobtained ultraviolet-absorbing film-attached glass plate were evaluatedin the same manner as in Example 1 except for the moisture resistancetest. The evaluation results are shown in Table 2.

Example 15

52.2 g of SOLMIX AP-1, 12.1 g of tetramethoxysilane, 3.8 g of3-glycidoxypropyltrimethoxysilane, 11.0 g of the silylated ultravioletabsorber solution obtained in the above Preparation Example, 9.5 g oflactic acid and 11.4 g of ion-exchanged water were charged and stirredfor one hour. Then, 4.94 g of SOLMIX AP-1 was added and stirred toobtain a coating solution 13 for forming an ultraviolet-absorbing film.An ultraviolet-absorbing film-attached glass plate was prepared in thesame manner as in Example 7 except that the above coating solution 13was used instead of the coating solution 6. The properties of theobtained ultraviolet-absorbing film-attached glass plate were evaluatedin the same manner as in Example 1 except for the moisture resistancetest. The evaluation results are shown in Table 2.

Example 16

61.5 g of SOLMIX AP-1, 12.1 g of tetramethoxysilane, 3.8 g of3-glycidoxypropyltrimethoxysilane, 11.0 g of the silylated ultravioletabsorber solution obtained in the above Preparation Example, 0.2 g ofmalonic acid and 11.4 g of ion-exchanged water were charged and stirredfor one hour. Then, 4.94 g of SOLMIX AP-1 was added and stirred toobtain a coating solution 14 for forming an ultraviolet-absorbing film.An ultraviolet-absorbing film-attached glass plate was prepared in thesame manner as in Example 7 except that the above coating solution 14was used instead of the coating solution 6. The properties of theobtained ultraviolet-absorbing film-attached glass plate were evaluatedin the same manner as in Example 1 except for the moisture resistancetest. The evaluation results are shown in Table 2.

Example 17

17.8 g of SOLMIX AP-1, 16.5 g of tetramethoxysilane, 5.3 g of3-glycidoxypropyltrimethoxysilane, 15.1 g of the silylated ultravioletabsorber solution obtained in the above Preparation Example, 0.3 g ofSR-SEP as epoxide, 15.6 g of acetic acid and 29.3 g of ion-exchangedwater were charged and stirred for one hour. Then, 4.94 g of SOLMIX AP-1was added and stirred to obtain a coating solution 15 for forming anultraviolet-absorbing film. An ultraviolet-absorbing film-attached glassplate was prepared in the same manner as in Example 7 except that theabove coating solution 15 was used instead of the coating solution 6.The properties of the obtained ultraviolet-absorbing film-attached glassplate were evaluated in the same manner as in Example 7. The evaluationresults are shown in Table 2.

Example 18

30.4 g of SOLMIX AP-1, 15.5 g of tetramethoxysilane, 4.9 g of3-glycidoxypropyltrimethoxysilane, 14.2 g of the silylated ultravioletabsorber solution obtained in the above Preparation Example, 1.2 g ofSR-SEP as polyepoxide, 4.3 g of methanol silica sol as colloidal silica,14.7 g of acetic acid and 14.7 g of ion-exchanged water were charged andstirred for one hour. Then, 4.94 g of SOLMIX AP-1 was added and stirredto obtain a coating solution 16 for forming an ultraviolet-absorbingfilm. An ultraviolet-absorbing film-attached glass plate was prepared inthe same manner as in Example 7 except that the above coating solution16 was used instead of the coating solution 6. The properties of theobtained ultraviolet-absorbing film-attached glass plate were evaluatedin the same manner as in Example 7. The evaluation results are shown inTable 2.

Example 19

43.3 g of ethanol, 21.8 g of tetramethoxysilane, 14.2 g of the silylatedultraviolet absorber solution obtained in the above Preparation Example,16.4 g of pure water and 4.3 g of a 1% nitric acid aqueous solution werecharged and stirred for one hour to obtain a coating solution 17 forforming an ultraviolet-absorbing film. An ultraviolet-absorbingfilm-attached glass plated was prepared in the same manner as in Example1 except that the above coating solution 17 was used instead of thecoating solution 1. The properties of the obtained ultraviolet-absorbingfilm-attached glass plate were evaluated in the same manner as inExample 1. The evaluation results are shown in Table 2.

Example 20

47.0 g of ethanol, 15.1 g of tetramethoxysilane, 5.1 g ofmethyltrimethoxysilane, 13.1 g of the silylated ultraviolet absorbersolution obtained in the above Preparation Example, 15.6 g of pure waterand 4.1 g of a 1% nitric acid aqueous solution were charged and stirredfor one hour to obtain a coating solution 18 for forming anultraviolet-absorbing film. An ultraviolet-absorbing film-attached glassplate was prepared in the same manner as in Example 1 except that theabove coating solution 18 was used instead of the coating solution 1,and the thickness of the ultraviolet-absorbing film after drying waschanged as shown in Table 2. The properties of the obtainedultraviolet-absorbing film-attached glass plate were evaluated in thesame manner as in Example 1. The evaluation results are shown in Table2.

Example 21

49.6 g of ethanol, 17.3 g of tetramethoxysilane, 9.6 g of3-glycidoxypropyltrimethoxysilane, 3.6 g of2,2′,4,4′-tetrahydroxybenzophenone, 15.8 g pure water and 4.2 g of a 1%nitric acid aqueous solution were charged and stirred for one hour toobtain a coating solution 19 for forming an ultraviolet-absorbing film.An ultraviolet-absorbing film-attached glass plated was prepared in thesame manner as in Example 1 except that the above coating solution 19was used instead of the coating solution 1 and the thickness of theultraviolet-absorbing film after drying was changed as shown in Table 2.The properties of the obtained ultraviolet-absorbing film-attached glassplate were evaluated in the same manner as in Example 1. The evaluationresults are shown in Table 2.

The compositions of the coating solutions for formingultraviolet-absorbing films obtained in the above Examples 1 to 21 aresummarized in Table 1. Here, in Table 1, abbreviations of the compoundsused represent the following compounds.

TMOS: Tetramethoxysilane

MTMS: Methyltrimethoxysilane

GPTMS: 3-Glycidoxypropyltrimethoxysilane

Si-THBP: Silylated ultraviolet absorber obtained in Preparation Example

THBP: 2,2′,4,4′-Tetrahydroxybenzophenone

TABLE 1 Solid content composition in coating solution for formingultraviolet-absorbing film (parts by mass) Ultraviolet Compound (c)Compound (a) Compound (b) absorber Resin, etc. Fine silica TMOS MTMSGPTMS Si-THBP THBP Type Amount particles Ex. 1 56.8 — 19.1 24.1 — — — —Ex. 2 56.8 — 19.1 24.1 — — — — Ex. 3 60.4 — 15.4 24.2 — — — — Ex. 4 49.9— 25.9 24.2 — — — — Ex. 5 59.9 — 10.1 30.0 — — — — Ex. 6 50.1 — 29.920.0 — — — — Ex. 7 55.0 — 18.7 26.2 — SR-SEP 4.4  7.7 Ex. 8 55.0 — 18.726.2 — SR-SEP 4.4  7.7 Ex. 9 55.9 — 17.6 26.4 — SR-SEP 1.0 14.2 Ex. 1053.4 — 19.5 27.1 — SR-SEP 4.1 15.5 Ex. 11 56.8 — 17.9 25.3 — SR-SEP 4.8— Ex. 12 56.8 — 17.9 25.3 — SR-SEP 4.8 — Ex. 13 56.7 — 17.9 25.3 —Glycerin 3.6 — Ex. 14 56.8 — 17.8 25.3 — — — — Ex. 15 56.8 — 17.8 25.3 —— — — Ex. 16 56.8 — 17.8 25.3 — — — — Ex. 17 56.5 — 18.2 25.3 — SR-SEP1.0 — Ex. 18 56.7 17.9 25.4 — SR-SEP 4.4 15.7 Ex. 19 75.8 — — 24.2 — — —Ex, 20 56.7 19.2 — 24.1 — — — Ex. 21 56.7 31.5 11.8 — — Contents of therespective components in coating solution for formingultraviolet-absorbing film Acid catalyst Water Compound (c) Protonconcentration Molar equivalents Content calculated in coating solutionto the amount, calculated as SiO₂ in coating solution Type [mol/kg] asSiO₂, of compound (c) [mass %] Ex. 1 Nitric acid 0.004 8.0 6.8 Ex. 2Nitric acid 0.004 8.0 6.8 Ex. 3 Nitric acid 0.004 8.0 7.1 Ex. 4 Nitricacid 0.004 8.0 6.1 Ex. 5 Nitric acid 0.005 8.0 6.5 Ex. 6 Nitric acid0.005 8.0 6.5 Ex. 7 Acetic acid 2.3 15.0 5.9 Ex. 8 Acetic acid 2.3 15.05.9 Ex. 9 Acetic acid 2.6 15.0 6.5 Ex. 10 Acetic acid 2.3 15.0 5.7 Ex.11 Nitric acid 0.005 8.0 6.1 Ex. 12 Acetic acid 2.4 8.0 6.1 Ex. 13Acetic acid 2.5 8.0 6.2 Ex. 14 Acetic acid 1.9 8.0 4.8 Ex. 15 Lacticacid 1.5 8.0 4.8 Ex. 16 Malonic acid 0.05 8.0 4.8 Ex. 17 Acetic acid 2.615.0 6.5 Ex. 18 Acetic acid 2.3 8.0 6.1 Ex. 19 Nitric acid 0.007 8.0 8.6Ex, 20 Nitric acid 0.005 8.0 5.9 Ex. 21 Nitric acid 0.036 8.0 6.8

TABLE 2 After accelerated After moisture weather Initial values Increase[%] resistance test resistance test Transmittance in haze valueTransmittance Transmittance Film [%] at Haze after abrasion [%] at [%]at thickness wavelength of value Scratch resistance wavelength ofwavelength of [nm] Crack 380 nm [%] test test Crack 380 nm Crack 380 nmEx. 1 2,500 ◯ 0.6 0.1 ◯ 3.5 ◯ 0.7 ◯ 17.5 Ex. 2 3,000 ◯ 0.4 0.1 ◯ 3.2 ◯0.4 ◯ 16.8 Ex. 3 2,400 ◯ 0.6 0.1 ◯ 3.0 ◯ 0 X — Ex. 4 2,750 ◯ 0.6 0.1 ◯3.8 ◯ 0.6 ◯ 18.0 Ex. 5 2,000 ◯ 0.5 0.1 ◯ 3.6 ◯ 0.6 ◯ 15.5 Ex. 6 2,800 ◯0.6 0.1 ◯ 3.0 ◯ 0.6 ◯ 16.8 Ex. 7 4,000 ◯ 0.4 0.1 ◯ 2.0 ◯ 0.3 ◯ 0.8 Ex. 86,500 ◯ 0.1 0.1 ◯ 1.9 ◯ 0.1 ◯ 0.2 Ex. 9 6,300 ◯ 0.1 0.1 ◯ 1.9 ◯ 0.1 ◯0.2 Ex. 10 6,000 ◯ 0.2 0.1 ◯ 2.0 ◯ 0.1 ◯ 0.3 Ex. 11 2,800 ◯ 0.6 0.4 ◯2.2 ◯ 0.5 ◯ 6.1 Ex. 12 3,200 ◯ 0.6 0.3 X 2.1 ◯ 0.5 ◯ 0.9 Ex. 13 3,100 ◯0.6 0.2 X 2.9 ◯ 0.7 ◯ 1.6 Ex. 14 2,600 ◯ 0.7 0.2 X 2.5 ◯ 0.9 ◯ 4.1 Ex.15 2,500 ◯ 0.8 0.1 X 2.9 ◯ 0.9 ◯ 5.5 Ex. 16 2,300 ◯ 0.9 0.2 X 3.1 ◯ 1.0◯ 7.6 Ex. 17 4,000 ◯ 0.4 0.1 X 1.9 ◯ 0.3 ◯ 0.5 Ex. 18 4,500 ◯ 0.8 0.1 X2.7 ◯ 0.7 ◯ 1.5 Ex. 19 2,400 X 0.7 0.1 ◯ 2.5 X Cracking — — Ex. 20 2,500X 0.6 0.1 ◯ 4.0 X 0.7 — — Ex. 21 3,500 ◯ 0.6 0.1 ◯ 3.2 X 3.5 X — *Themoisture resistance test conditions in Examples 7 to 18 are 50° C. and arelative humidity of 95%, and the moisture resistance test conditions inother Examples are 80° C. and a relative humidity of 95%.

As shown in Table 2, the ultraviolet-absorbing films prepared inExamples 19 to 21 being comparative examples, cracks were formed, andthe mechanical properties were inadequate, although the ultravioletabsorbing ability was obtained. On the other hand, it is evident thatthe ultraviolet-absorbing films prepared in Examples 1 to 18 beingworking examples of the present invention, are excellent in theultraviolet-absorbing ability, and also excellent in mechanicalproperties such as the abrasion resistance, cracking resistance, etc.

Further, the ultraviolet-absorbing films prepared in Examples 7 to 18are ones wherein a polyepoxide or glycerin was contained in the coatingcomposition as the film-forming material, and/or a weak acid having apKa1 of from 1.0 to 5.0 was used as an acid catalyst, and they areultraviolet-absorbing films excellent in light resistance havingformation of cracks or deterioration of the ultraviolet-absorbingability after the accelerated weather resistance test suppressed.Further, the ultraviolet-absorbing films prepared in Examples 1 to 11are ones wherein a strong acid (nitric acid) was used as the acid, or apolyepoxide or glycerin was contained in the coating composition as thefilm-forming material, and in addition, a weak acid (acetic acid) wasused as an acid catalyst, and further, fine silica particles and waterwere incorporated in proper amounts, and it is evident that they have acertain hardness and are excellent in the scratch resistance.

INDUSTRIAL APPLICABILITY

The ultraviolet-absorbing glass article of the present invention hasexcellent ultraviolet-absorbing property and mechanical durability andis applicable to a site where mechanical durability such as abrasionresistance, cracking resistance, etc. are highly required, such as adoor glass plate for automobiles.

This application is a continuation of PCT Application No.PCT/JP2010/058215 filed on May 14, 2010, which is based upon and claimsthe benefit of priority from Japanese Patent Application No. 2009-118259filed on May 15, 2009. The contents of those applications areincorporated herein by reference in its entirety.

What is claimed is:
 1. A coating solution for forming an ultraviolet-absorbing film, which comprises a combination of the following three components: a component derived from an epoxidized organooxysilane compound (a), a component derived from an organooxysilane compound (b) which is a reaction product of a hydroxylated benzophenone compound and an epoxidized organooxysilane compound, and a component derived from an organooxysilane compound (c) other than the above (a) and (b), wherein each of the above three components is the corresponding organooxysilane compound of the above (a), (b) or (c), or a constituting component of a partially hydrolyzed condensate of at least the corresponding organooxysilane compound of the above (a), (b) or (c).
 2. The coating solution for forming an ultraviolet-absorbing film according to claim 1, wherein the proportions of the component derived from the organooxysilane compound (a), the component derived from the organooxysilane compound (b) which is a reaction product of a hydroxylated benzophenone compound and an epoxidized organooxysilane compound, and the component derived from the organooxysilane compound (c) other than the above (a) and (b) are such proportions that, based on 100 parts by mass of the total solid content of the component derived from the organooxysilane compound (a), the component derived from the organooxysilane compound (b) which is a reaction product of a hydroxylated benzophenone compound and an epoxidized organooxysilane compound, and the component derived from the organooxysilane compound (c) other than the above (a) and (b), the component derived from the organooxysilane compound (a) is from 5 to 50 parts by mass, the component derived from the organooxysilane compound (b) is from 10 to 50 parts by mass, and the component derived from the organooxysilane compound (c) is from 40 to 80 parts by mass.
 3. The coating solution for forming an ultraviolet-absorbing film according to claim 1, which contains at least one member selected from polyepoxides and glycerin.
 4. The coating solution for forming an ultraviolet-absorbing film according to claim 3, wherein the content of said at least one member selected from polyepoxides and glycerin is from 0.1 to 20 parts by mass, based on 100 parts by mass of the total solid content of the component derived from the organooxysilane compound (a), the component derived from the organooxysilane compound (b) which is a reaction product of a hydroxylated benzophenone compound and an epoxidized organooxysilane compound, and the component derived from the organooxysilane compound (c) other than the above (a) and (b).
 5. The coating solution for forming an ultraviolet-absorbing film according to claim 1, which contains an acid having a primary proton pKa of from 1.0 to 5.0 in a proportion of from 0.005 to 5.0 mol/kg as the molar concentration, based on the total mass of the coating solution, of the proton when the primary proton of the acid is completely dissociated.
 6. The coating solution for forming an ultraviolet-absorbing film according to claim 1, which contains fine particles of silica in a proportion of from 0.5 to 50 parts by mass, based on 100 parts by mass of the total solid content of the component derived from the organooxysilane compound (a), the component derived from the organooxysilane compound (b) which is a reaction product of a hydroxylated benzophenone compound and an epoxidized organooxysilane compound, and the component derived from the organooxysilane compound (c) other than the above (a) and (b), and water in a proportion of from 8 to 20 equivalents by molar ratio to the amount, calculated as SiO₂, of the component derived from the organooxysilane compound (c).
 7. The coating solution for forming an ultraviolet-absorbing film according to claim 1, wherein the content of the component derived from the organooxysilane compound (c) is from 1 to 10 mass % as the SiO₂ content when silicon atoms contained in this component are calculated as SiO₂.
 8. An ultraviolet-absorbing glass article comprising a glass substrate and an ultraviolet-absorbing film formed on at least part of the glass substrate surface by using the coating solution for forming an ultraviolet-absorbing film as defined in claim
 1. 9. The ultraviolet-absorbing glass article according to claim 8, wherein the transmittance of light having a wavelength of 380 nm through the glass article is at most 7.0%.
 10. The ultraviolet-absorbing glass article according to claim 8, wherein when an abrasion test of 1,000 rotations with a CS-10F abrasive wheel is applied against the surface of the ultraviolet-absorbing film in accordance with JIS-R3212 (1998), the increase in the haze after the test as compared to before the test is at most 5.0%. 